WOW what an article !!! Thanks and looking forward to more . BUT (there's that word again ) this also inspires me to think what would this gun be like in the opposite direction IE: 10.5 FPE ? HMMMM good enough excuse to buy my own HW90 .
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HW90 potential
- Thread starter JayJay
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Somewhere along the way, I will do some testing at below 12fpe as I know Brits and others would like to know what it will do with these (hopefully good) mods. The Brits are limited to 12fpe and in my beloved France the limit is 20 joules (14.75fpe) without getting special licenses. I should have my gun back together to resume testing next week, God willing. I appreciate the continuing interest of everyone. Charles
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What's the caliber and the year? What happened to the stock?
Yes, the HW90/RX series is definitely an acquired taste.
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I didn't know that France has a 20 joule limit. I never understood springer airgun power limits. A bow is probably more dangerous, and easier to fire rapidly. They're also easier to crank up the power. My wife has a compound bow with power adjustable arms. She can get off several shots in the time it takes to cock and load a breakbarrel. When the Schrader valves arrive, I'll pop one in and maybe run some low power chrony tests.
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Excellent. The packages were mailed yesterday to all, but I was told they would actually leave the PO today as not mailed in the AM (I live in a town so small, we are lucky to even have a PO).
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Very good question. You might try to find a real English HW90K (short barrel carbine). I checked with Krale about a year ago. They can get one but it might take several months.
Here's a great youtube video: English HW90K
I wish Weihrauch made a scaled down HW90 for the low power market. Something about the size and weight of an HW30. But then there's a real danger that people would over-charge the ram, possibly causing accidents and legal problems. In contrast, the HW90 is basically self-limiting. If you overcharge it, you make it uncomfortably difficult or impossible to cock. Also, Weihrauch fits a piston seal that simply refuses to deliver more than about 21 fpe to the pellet. That has to be intentional.
Because the HW90 piston is a side latcher (the trigger latches onto the side of the piston rather than onto a tailhook) it may be feasible to make your own piston. It's simpler, you don't need to add a trigger hook. So that opens up the possibility of making light weight pistons, short stroking it, alternate piston seals, etc. Heck, I should buy a little hobby lathe. Although, the thought of boring out a steel cylinder with a tiny little boring bar... it would take dozens of passes, a few thou at a time. Hmmm.
I'll try some low power runs shortly, with different pellets.
Here's another thought... It may be that the Theoben inertia weight works best at low power. Considering that Theoben was an English company.
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I got in more high quality schrader valve cores in case someone here has a need. These were chosen to meet the high pressure needs in our HW90 guns. They are USA made Dill 302-DN. They open at 80psi and are rated 2000psi. They are meant to be used in high pressure struts and the like. Easy to install -- plug and play in the HW90. My original core was leaking, brand new. No problems since screwing this one in. These are a simple gift to you who also own an HW90. Just PM me should you want one with your shipping address and I'll let you know when it ships. Charles
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I have news:
No-where on the internet, as if by some secret plot (*lol), is to be easily discovered the correct dimensions of the o-ring "pair" used on the HW90 which are seated "inside" the piston at the rear, one being backed up by a white delrin backer for reinforcement.... until now!
One, they are NOT: 15/16" ID Nominal X 1-1/8" OD Nominal X CS Nominal 3/32"-That is much too large to work right as I now well know!
The proper sizing is metric and these two black o-rings both measure 23mmID x 28mmOD x CS 2.5mm. That's it! They are a soft, very flexible and slightly grippy material. I am not expert enough to say of what they are made, but silicone came to mind. I'm sure on the dimensions, not on the material.
The very nice teflon ecapsulated viton orings that I bought in dimensions 15/16" ID Nominal X 1-1/8" OD Nominal X CS Nominal 3/32" were much to large with that stiff outer shell to ever fit and seal. But I must say that, even though too large, I slid one over the inner, black compression tube, squeezing hard and there was almost no friction! So, I may continue to seek something teflon that will work to have lowest and most consistent friction, but that may be a pipe dream as I can't locate an o-ring in this size that is just coated in teflon with a soft center needed to seal in the air. Solid teflon would never keep in the air pressure.
No-where on the internet, as if by some secret plot (*lol), is to be easily discovered the correct dimensions of the o-ring "pair" used on the HW90 which are seated "inside" the piston at the rear, one being backed up by a white delrin backer for reinforcement.... until now!
One, they are NOT: 15/16" ID Nominal X 1-1/8" OD Nominal X CS Nominal 3/32"-That is much too large to work right as I now well know!
The proper sizing is metric and these two black o-rings both measure 23mmID x 28mmOD x CS 2.5mm. That's it! They are a soft, very flexible and slightly grippy material. I am not expert enough to say of what they are made, but silicone came to mind. I'm sure on the dimensions, not on the material.
The very nice teflon ecapsulated viton orings that I bought in dimensions 15/16" ID Nominal X 1-1/8" OD Nominal X CS Nominal 3/32" were much to large with that stiff outer shell to ever fit and seal. But I must say that, even though too large, I slid one over the inner, black compression tube, squeezing hard and there was almost no friction! So, I may continue to seek something teflon that will work to have lowest and most consistent friction, but that may be a pipe dream as I can't locate an o-ring in this size that is just coated in teflon with a soft center needed to seal in the air. Solid teflon would never keep in the air pressure.
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And should anyone wish to try a low friction o-ring just behind the piston seal, the one which will fit must be 28mmID x 30mmOD, metric again, meaning the cross-section is 1mm. The only place that has them in stock to my knowledge is oringsandmore.com part number 281MMP in hard, pure PTFE. I measured with a high precision Mitutoyo vernier caliper, model 530-118 -- very nice item. To make this hard o-ring work, it may not want to stretch over the 29.5mm piston. So, I may have to install it like a backer o-ring by making an angled slit in it -- it can't escape once installed and it's not there primarily to push air, but to simply keep the piston perfectly centered in front and maybe catch some blow-by air, second. Anyway, it's a cheap experiment!
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If not too boring, I would like to restate the case why is may make sense to put an o-ring into the slot behind the piston seal that was clearly made to take just such an o-ring. So much so, that when I first saw this groove, I thought Weihrauch workers had missed installing mine! So, why put an o-ring there?
1. The outer diameter of most of the piston is 29.5mm, except for two slightly raised bands near the rear which are 29.68mm wide. The inside diameter of the receiver tube is 30mm, so those two raised bands are to help center the piston's rear. At the front of the piston, only a thin-lipped, forward-most part of the piston seal actually touches the 30mm receiver tube in front -- the rest of the piston seal edge does not touch, at least with the Vortek seal. This means that the most important part of your piston seal (the edge) that actually seals against the cylinder tube, becomes subjected to wear and abuse, being called upon to stabilize this heavy piston moving with enough force that it would likely kill anyone, if allowed to simply slam into their chest instead of the air cushion at the transfer port. I guess what I'm trying to say is that it is hard to put into words the tremendous violence to which the piston and its seal, are exposed with every shot -- the relatively loose piston seal (it can rotate quite easily, both Vortek and Weihrauch seals) thin lipped outermost edge is literally bouncing off the walls at a speed some say to be 80 fps, rotating a touch perhaps, then goes under expanding pressure as it slams home the compressed air, quite free to wear itself against the cylinder walls unevenly, resulting in areas where the seal is no longer very circular, thus leading to irregular and ever changing small amounts of air blow-by. Also, and this surprised me, I noticed ding marks behind the piston seal area which indicates the piston metal hitting hard on the cylinder walls, both from forward motion AND rebound bounce. Nothing dramatic, mind you, but know that should the cylinder get dinged, as well, that would not be good as it would contribute to wearing your piston seal edge.
2. OK. So, what do we hope to gain by installing an o-ring where one may quite easily be added. I mean, you can pick up 5 - 28mmx30mm viton o-rings on Amazon for about $7., but only need one.
a) The right o-ring will be proud of the surrounding piston steel by just 0.25mm --- all around its circumference, mating quite perfectly with the 30mm inside of your receiver's cylinder, obviously keeping the piston front quite perfectly centered, meaning there will be no chance for the front steel of the piston ever being able to ding itself against the cylinder wall. Now, I think that sort of dinging is highly rare -- likely only when (for whatever reason) you get a detonation -- it takes only a truly minuscule amount of oil or volatile vapor to create quite the bang. It can happen and did happen to me. With this o-ring, no dings are possible, whatever the cause since your piston is now made to run straight and true. And yes, the piston seal, also being 30mm diameter, helps keep things straight as well, but no longer has to wear itself in doing so alone -- the o-ring can do that now, but kept well lubed, it should last an awful long time since the o-ring is not subjected to the other abuses encountered by the piston seal.
b) Piston seal edge wear and dings (which can all affect long term accuracy of the gun and longevity of the piston seal) should be reduced by at least 50% and likely much more since you've now doubled the area responsible for keeping your piston well-centered.
c) As the piston slams home toward the transfer port, now better centered, it will still expand slightly, creating the desired seal, but as better centered, creating a more balanced sealing all around, not stronger on one edge than another because in that 1/5000 second it got caught slightly misaligned and locked in that misalignment through the pressurization phase of the firing cycle.
d) Something easier to imagine, perhaps, is that you can now have a more generous application of a wonderful, non-detonating lube, like Krytox, applied BEHIND the o-ring area of the cylinder wall without fear it will easily get past the piston seal and basically disappear, leaving your cylinder dry, leading to the ever-increasing friction and wear and inaccuracy that a drying cylinder entails. I still wouldn't use any lube that can possibly lead to detonation, however. Need some Krytox? Check my classified ad that I hope to put in soon -- (I'm such a slacker!). This is the surest benefit to popping an o-ring into that empty groove.
e. The o-ring will not only keep your lube away from the piston seal and compression chamber, but it will keep dust, dirt, moisture and any other crud out, as well, creating another line of defense against every contamination.
f. Anything we can do to keep the piston seal in good shape will lead to greater repeatability, shot to shot, making accuracy maybe just that touch better.
3. What are the negatives to adding this o-ring? More friction -- lowering pellet velocity, but with good lube, it may not even be noticed as the "dynamic" drag of such an o-ring (moving very fast, that is) especially a lubed o-ring made of teflon or viton, would be about the same as ice -- and we all know how that goes. I can't think of any other negatives. Can you? Of course, there is always the risk of a vapor lock between the o-ring and the piston seal, leading inevitably to the complete and utter annihilation of every squirrel in your neighborhood-- but them's the risks we takes!
1. The outer diameter of most of the piston is 29.5mm, except for two slightly raised bands near the rear which are 29.68mm wide. The inside diameter of the receiver tube is 30mm, so those two raised bands are to help center the piston's rear. At the front of the piston, only a thin-lipped, forward-most part of the piston seal actually touches the 30mm receiver tube in front -- the rest of the piston seal edge does not touch, at least with the Vortek seal. This means that the most important part of your piston seal (the edge) that actually seals against the cylinder tube, becomes subjected to wear and abuse, being called upon to stabilize this heavy piston moving with enough force that it would likely kill anyone, if allowed to simply slam into their chest instead of the air cushion at the transfer port. I guess what I'm trying to say is that it is hard to put into words the tremendous violence to which the piston and its seal, are exposed with every shot -- the relatively loose piston seal (it can rotate quite easily, both Vortek and Weihrauch seals) thin lipped outermost edge is literally bouncing off the walls at a speed some say to be 80 fps, rotating a touch perhaps, then goes under expanding pressure as it slams home the compressed air, quite free to wear itself against the cylinder walls unevenly, resulting in areas where the seal is no longer very circular, thus leading to irregular and ever changing small amounts of air blow-by. Also, and this surprised me, I noticed ding marks behind the piston seal area which indicates the piston metal hitting hard on the cylinder walls, both from forward motion AND rebound bounce. Nothing dramatic, mind you, but know that should the cylinder get dinged, as well, that would not be good as it would contribute to wearing your piston seal edge.
2. OK. So, what do we hope to gain by installing an o-ring where one may quite easily be added. I mean, you can pick up 5 - 28mmx30mm viton o-rings on Amazon for about $7., but only need one.
a) The right o-ring will be proud of the surrounding piston steel by just 0.25mm --- all around its circumference, mating quite perfectly with the 30mm inside of your receiver's cylinder, obviously keeping the piston front quite perfectly centered, meaning there will be no chance for the front steel of the piston ever being able to ding itself against the cylinder wall. Now, I think that sort of dinging is highly rare -- likely only when (for whatever reason) you get a detonation -- it takes only a truly minuscule amount of oil or volatile vapor to create quite the bang. It can happen and did happen to me. With this o-ring, no dings are possible, whatever the cause since your piston is now made to run straight and true. And yes, the piston seal, also being 30mm diameter, helps keep things straight as well, but no longer has to wear itself in doing so alone -- the o-ring can do that now, but kept well lubed, it should last an awful long time since the o-ring is not subjected to the other abuses encountered by the piston seal.
b) Piston seal edge wear and dings (which can all affect long term accuracy of the gun and longevity of the piston seal) should be reduced by at least 50% and likely much more since you've now doubled the area responsible for keeping your piston well-centered.
c) As the piston slams home toward the transfer port, now better centered, it will still expand slightly, creating the desired seal, but as better centered, creating a more balanced sealing all around, not stronger on one edge than another because in that 1/5000 second it got caught slightly misaligned and locked in that misalignment through the pressurization phase of the firing cycle.
d) Something easier to imagine, perhaps, is that you can now have a more generous application of a wonderful, non-detonating lube, like Krytox, applied BEHIND the o-ring area of the cylinder wall without fear it will easily get past the piston seal and basically disappear, leaving your cylinder dry, leading to the ever-increasing friction and wear and inaccuracy that a drying cylinder entails. I still wouldn't use any lube that can possibly lead to detonation, however. Need some Krytox? Check my classified ad that I hope to put in soon -- (I'm such a slacker!). This is the surest benefit to popping an o-ring into that empty groove.
e. The o-ring will not only keep your lube away from the piston seal and compression chamber, but it will keep dust, dirt, moisture and any other crud out, as well, creating another line of defense against every contamination.
f. Anything we can do to keep the piston seal in good shape will lead to greater repeatability, shot to shot, making accuracy maybe just that touch better.
3. What are the negatives to adding this o-ring? More friction -- lowering pellet velocity, but with good lube, it may not even be noticed as the "dynamic" drag of such an o-ring (moving very fast, that is) especially a lubed o-ring made of teflon or viton, would be about the same as ice -- and we all know how that goes. I can't think of any other negatives. Can you? Of course, there is always the risk of a vapor lock between the o-ring and the piston seal, leading inevitably to the complete and utter annihilation of every squirrel in your neighborhood-- but them's the risks we takes!
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g. Almost forgot this benefit: the piston seal is always going to allow some super compressed air to blow backwards with each shot. How much? Who knows. The same amount blowing by each shot? No. It must necessarily vary. Now, the air space or volume between the piston seal edge and this theoretical o-ring is very, very small as a percentage of the total volume of air at atmospheric pressure, but we must more accurately consider the very small, but relatively "heavy!" super-compressed air volume that is blowing by your piston seal. As that volume is now made very small, any of it blowing by your piston seal is potentially significant! due to it being highly pressurized air. Thus, the point being made is that with a good 28mmIDx30mmOD o-ring just behind your piston seal, hardly any of this compressed blow-by air will be allowed to blow by the new o-ring just behind it, thus theoretically reducing the amount of blow by each shot to no more than the amount needed to balance the air pressure between the piston seal edge and the o-ring edge. This should make for more consistency, shot to shot, of air going through your transfer port and thus, a touch better accuracy, all other variables being excluded from consideration. Stay tuned for: Improved accuracy on the fly or bye-bye blow- by.
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I would like to think my little joke about the evils of "vapor lock", three posts up, made you smile a little. However, what I was jokingly alluding to there is actually a possible reason Weihrauch didn't choose to use this o-ring groove, after all, but simply left the groove empty, perhaps after testing. What? Well, in the case that you have worn-in your piston seal so that it really is sealing extremely well AND you add an o-ring behind it that is also sealing extremely well, what could go wrong with that? The piston seal may seal almost perfectly with one exception. Can you guess what that would be? The weather right now is 72 degrees and sunny in Ellsworth, Kansas (that distraction was to give you time to think). Even in a precision automotive engine cylinder with multiple o-rings on each piston, there is blow-by exhaust which goes into your crank area instead of out your exhaust. In the HW90, at least at the moment of highest, piston-slamming, peak chamber pressure, some compressed air will leak backwards past the piston seal, as previously mentioned in the above post. This high pressure, leaked air can basically "pressurize" the tiny space between the cylinder wall and the piston, beginning where the piston seal touches the cylinder wall in front and ending where the o-ring touches the cylinder wall behind. So, after the pellet has left the rifle and everything comes to rest, you could be left with some pressurized air being "locked" in that tiny space. So, why care about that? Let's just say it's an unintended, uninvited consequence which could cause problems while giving no clear benefit. I can imagine some issues, but why bother when this unwanted pressurization is easily avoided. In the case of the o-ring that I chose, which is pure teflon that's rigid and hard like plastic, just cut it at say a 60 degree angle in any one place along its circumference and voila -- it will quickly, but not instantaneously, release any blow-by air pressure that comes its way. Also, cutting will make it extremely easy to install this o-ring into its groove which would be a losing struggle, I believe, even were you to heat the teflon and freeze the piston, the inelastic nature of teflon means that it would likely be stretched forever by forcing its 28mmID over the piston's 29.5mm OD and into the groove. So, just cut it and pop it in place. It is so rigid, it will still look like a near-perfect circle and once the piston goes back into the cylinder, there is no way it can fall out. It will still provide all the benefits we want, but be easy to install and not suffer "vapor lock". And the squirrels will thank you.
p.s. In cutting the o-ring with a sharp razor blade, it is important not to lay the o-ring flat and then cut it, but rather, stand it upright and then cut it at the bottom at say 60 degrees. This cut will act to temporarily "seal" when hit by high blow-back pressure, limiting blow-back as desired, but then release the pressure when at rest. And should you remain credulous, here is one bad thing that could happen with an o-ring that seals darn good: The locked, pressurized air would easily get under and inside the walls of your piston seal, with each shot adding more air pressure as your seal (which is soft enough to be compressed between strong fingers) distorts its shape, maybe enough to be eventually ruined. Ah yes, the old seal popping off the end of the piston trick!
p.s. In cutting the o-ring with a sharp razor blade, it is important not to lay the o-ring flat and then cut it, but rather, stand it upright and then cut it at the bottom at say 60 degrees. This cut will act to temporarily "seal" when hit by high blow-back pressure, limiting blow-back as desired, but then release the pressure when at rest. And should you remain credulous, here is one bad thing that could happen with an o-ring that seals darn good: The locked, pressurized air would easily get under and inside the walls of your piston seal, with each shot adding more air pressure as your seal (which is soft enough to be compressed between strong fingers) distorts its shape, maybe enough to be eventually ruined. Ah yes, the old seal popping off the end of the piston trick!
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Today, I received in Viton o-rings to potentially replace the two o-rings which go in the end of the HW90 piston. The originals were more supple with less friction than the Viton. The Viton were more slightly more rigid and less compressible by about 50%, but the added friction has me decided to leave well enough alone and just put the black stock o-rings back in. Still waiting on the 28x1mm teflon ring to go behind the piston seal to arrive by end of the week.
More updates to come.....
More updates to come.....
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I seriously considered 20 cal as I thought it might be the best overall to my needs. It was only pellet choices in .22 that swayed me that way. My take is the Beeman versions had even better QC -- but at a price, of course. I've had a number of minor issues with my Weihrauch. I like it very much, but realize not many others would put up with screws shaking loose, piston seal burning holes in weeks due to factory lube detonation, leaking schrader valve core and a trigger seriously needing attention to shoot safely -- all out of the box new. So, here we are because we think it's worth making right as the basic design and precision machining is too good not to -- and I really do like mine now that I have the issues under control, including the trigger that I now like, too!
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I tried fitting the 28mmx30mmx1mm teflon o-ring to the empty groove on the HW90 piston. The o-ring was spec'd at 28mmID and the groove is precisely 28mm, but the o-ring had an ID which was larger than 28mm, so it didn't seat tightly in the groove. In other words, it didn't work as the piston wouldn't fit in the receiver cylinder with it in place. Oh well.....
I'm not giving up on this just yet -- I now have a couple 27x29x1mm silicone o-rings coming in via eBoy. We'll see how that size fits. The silicone should stretch enough to go on and the 1mm cross section should be just slightly reduced which may help it go into the receiver cylinder. We'll see......
I'm not giving up on this just yet -- I now have a couple 27x29x1mm silicone o-rings coming in via eBoy. We'll see how that size fits. The silicone should stretch enough to go on and the 1mm cross section should be just slightly reduced which may help it go into the receiver cylinder. We'll see......
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Still waiting on o-rings to go "just" behind the piston seal in that groove, but I have something to share: When I tried fitting the teflon 28x30x1mm o-ring, it was too loose, but I decided to cut it and see how that would go...... not well. It was still a very tight fit but I did get it to go into the receiver's compression tube, and then discovered something interesting: When I later removed that o-ring and piston from the compression tube , the teflon o-ring was torn or cut somehow into two pieces!! I asked myself how that could have happened and felt inside the receiver's cylinder bore and discovered where the trigger goes through the receiver and where the cocking shoe rides there are very sharp cut-outs in the receiver cylinder bore -- sharp enough to cut anything that is soft that passes it tightly, like a new piston seal! I mean, these are unrelieved cuts which are darn sharp.
My new Vortek piston seal which is a perfect 30mm in diameter (same as the cylinder into which it goes) could very easily have an edge permanently damaged by passing those sharp edges, just as my hard teflon o-ring was torn in two by those sharp edges.
Thus, I suggest that should you ever remove your piston, why not take a strip of rouge cloth, glue it onto a wooden popsicle stick and gently break and smooth those edges inside your cylinder bore at a 45% angle -- that should do it and give some peace of mind that when you reinstall your piston that the seal won't be scraped on its edge which could create a space where compressed air will blow by each shot.
Just for giggles, I installed the two new Viton o-rings inside the piston and put on the delrin backer and decided to see how it feels compared with the factory o-rings which I think are silicone rubber. Well, I noted a few things: 1. The new o-rings went in place easily. 2. When lubed, the piston slid onto what I will call the "compression tube" which contains the schader valve core, a bit tighter than with the original o-rings, but not excessively tight, just nice and snug. 3. Sliding motion is slick and smooth, but these o-rings do have a tendency to stick a touch at first until you "break" the grip which is easily done, so I don't think that's a worry. 4. I also noticed that these two o-rings (being significantly less compressible and harder) seemed to be keeping the piston more rigidly parallel with the compression tube than did the factory o-rings, which I think it a good thing as it means the piston will shoot more precisely down toward the transfer port with each shot being slightly more repeatable. 5. I'm now looking forward to seeing how the cocking of the HW90 "feels" with these Viton o-rings. If it feels good or better to cock and no problems noted in chrony velocity numbers, AND assuming they keep air pressure well as they should, I'll keep them in. Viton rings and seals are very durable. Many auto makers use Viton crankshaft and tranny seals, for instance, which must withstand many millions of rpms without leaking. 6. Of course, if actual use finds cocking effort to be impossible or some other fail, you'll be the second to know -- haha!
My new Vortek piston seal which is a perfect 30mm in diameter (same as the cylinder into which it goes) could very easily have an edge permanently damaged by passing those sharp edges, just as my hard teflon o-ring was torn in two by those sharp edges.
Thus, I suggest that should you ever remove your piston, why not take a strip of rouge cloth, glue it onto a wooden popsicle stick and gently break and smooth those edges inside your cylinder bore at a 45% angle -- that should do it and give some peace of mind that when you reinstall your piston that the seal won't be scraped on its edge which could create a space where compressed air will blow by each shot.
Just for giggles, I installed the two new Viton o-rings inside the piston and put on the delrin backer and decided to see how it feels compared with the factory o-rings which I think are silicone rubber. Well, I noted a few things: 1. The new o-rings went in place easily. 2. When lubed, the piston slid onto what I will call the "compression tube" which contains the schader valve core, a bit tighter than with the original o-rings, but not excessively tight, just nice and snug. 3. Sliding motion is slick and smooth, but these o-rings do have a tendency to stick a touch at first until you "break" the grip which is easily done, so I don't think that's a worry. 4. I also noticed that these two o-rings (being significantly less compressible and harder) seemed to be keeping the piston more rigidly parallel with the compression tube than did the factory o-rings, which I think it a good thing as it means the piston will shoot more precisely down toward the transfer port with each shot being slightly more repeatable. 5. I'm now looking forward to seeing how the cocking of the HW90 "feels" with these Viton o-rings. If it feels good or better to cock and no problems noted in chrony velocity numbers, AND assuming they keep air pressure well as they should, I'll keep them in. Viton rings and seals are very durable. Many auto makers use Viton crankshaft and tranny seals, for instance, which must withstand many millions of rpms without leaking. 6. Of course, if actual use finds cocking effort to be impossible or some other fail, you'll be the second to know -- haha!
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