Beeman Beeman R-7 .20 cal rebuild….. results….?

[Mycapt65]

Dieseling , I don’t believe so. I have heard a dieseling gun before . I put a tin or 2 of pellets through it since the rebuild about 2 years ago. I moved and everything was a mess for awhile.
I’ve been working on some other Airguns recently. So I took it out of the case and shot this video. It’s only 2 shots but it’s close to what I had recorded back then. I have no knowledge of the r-9 I don’t have one …yet…lol
but I do believe it’s basically the same gun with the exception of the screw in block. I can tell you that the tube on my r-10 was like a mirror finish inside. It was manufactured in 1987. I’m the original owner. I did polish everything inside and used limited moly and Tom’s red goo on the spring sparingly. The other guns I have worked on so far have a cross check in the tubes like a cylinder block in an engine. Does that matter ..who now’s. These things are finicky for sure. I remember back in the day guys were getting over 900 fps from 124’s ….as for the chronograph… I couldn’t say. In not an engineer . I only shot through it and record the numbers.
it shore isn’t helping my r-7 at the moment…

I'll have to look up the B&S on the R10s. If it's the same as the 95 something is a skew. A perfect comp tube combined with an efficient barrel will produce unusual power levels. My wiifes 177 Hw30 makes 9 fpe when all the others I've done make ~8.3 fpe with the same parts. Still a perfect comp comp tube is only worth so much and the combination of it with an exceptionally efficient barrel is extremely rare.

I'm not trying to rain on your parade. I'm just trying to understand if my information is right. When guns diesel it's silent. What you heard that is often mistaken for dieseling was detonation. That's very loud, adds a lot of velocity and shortens the life of the gun.

Dieseling is pretty much silent. Dieseling is a slower more controled burn of lubricants that increase cylinder pressure and that boosts velocity. The obvious sign of dieseling is smoke coming from the muzzle and or breech after a shot. Dieseling has to be pretty excessive for this smoke to be noticeable in normal conditions. The way to check for dieseling is to break the barrel after a shot and point it up to the sky and look through the bore. A clean running gun that doesn't appreciably diesel will have a completey clear view of the sky through the bore. If it's dieseling the view down the the barrel will be anywhere between completely dark to a light orange glow.

All spring guns (including mine) that are lubed with petroleum based lubricants diesel to some degree. But it should be undetectable. As in you should have a clear blue sky through the barrel after a shot. That is a clean running gun and imo important for consistent accuracy.

Be well
Ron

 

[Mycapt65]

I bought my .22 HW30 used. The numbers that I'm getting are very impressive compared to the ones that I'm seeing here. I haven't opened it up yet, but I plan to because it's a buzzer. It's an incredibly smooth and accurate rifle. Now I'm curious. 7 - 8 ft/lbs should be about right for a power tune. My PG4 fitted .177 is getting 9.5 ft/lbs

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9.5 fpe for a 177 Hw30 is exceptional. You're getting 8.3 out of a 22 hw30. Which is about normal. I've tuned a few and the 22s are hit or miss with barrel efficiency. A good one will do 9 fpe. You're a bright man so I'm sure you know that larger bores tend to be more efficient than smaller bores on piston guns. The problem with 22 Hw30s is the larger bore exhausts the relatively small swept volume too quickly for that potential efficiency to be useful. Combine that with Weihrauch's propensity for sloppy 22 barrels and you get what you got. It will pick up some power with a PG4 kit and VAC seal but it's unlikely it'll make as much power as your 177. I hope you prove me wrong. They're great guns and nobody loves them more then me. I've tuned several of them in 177, 20 and 22. All of mine are 177 for a reason.

 

[Pellets&Pistons-(Razor62)]

9.5 fpe for a 177 Hw30 is exceptional. You're getting 8.3 out of a 22 hw30. Which is about normal. I've tuned a few and the 22s are hit or miss with barrel efficiency. A good one will do 9 fpe. You're a bright man so I'm sure you know that larger bores tend to be more efficient than smaller bores on piston guns. The problem with 22 Hw30s is the larger bore exhausts the relatively small swept volume too quickly for that potential efficiency to be useful. Combine that with Weihrauch's propensity for sloppy 22 barrels and you get what you got. It will pick up some power with a PG4 kit and VAC seal but it's unlikely it'll make as much power as your 177. I hope you prove me wrong. They're great guns and nobody loves them more then me. I've tuned several of them in 177, 20 and 22. All of mine are 177 for a reason.

Did you happen to catch my most recent video featuring the HW30 in .22 cal. If not, check it out. The 25 yard, 5 shot group it produced is pretty impressive. Especially, when you consider who was behind the trigger...

 

[Mycapt65]

Did you happen to catch my most recent video featuring the HW30 in .22 cal. If not, check it out. The 25 yard, 5 shot group it produced is pretty impressive. Especially, when you consider who was behind the trigger...

That's great. BTW When i say Weihrauch 22 barrel efficiency is hit and miss. I wasn't talking about accuracy I was talking about power output. They can vary more in power output than 20 or 177. Probably because the same percentage of machining tolerance on a bigger bore makes for bigger changes in efficiency. This is only a guess on my part.

 

[Pellets&Pistons-(Razor62)]

That's great. BTW When i say Weihrauch 22 barrel efficiency is hit and miss. I wasn't talking about accuracy I was talking about power output. They can vary more in power output than 20 or 177. Probably because the same percentage of machining tolerance on a bigger bore makes for bigger changes in efficiency. This is only a guess on my part.

Perhaps, but there are .22 bores that will produce match grade accuracy. I've heard many complaints about Weihrauch .22 barrels. However, in my personal experience, I own at least 9 HW rifles in .22 and they're all up to 1/2" spinners at 50 yards. That includes the 2 little 30s. albeit, it requires a ridiculously big elevation adjustment and a little holdover to boot. I don't profess to have a clue as to why my mileage is different.

 

[Mycapt65]

Perhaps, but there are .22 bores that will produce match grade accuracy. I've heard many complaints about Weihrauch .22 barrels. However, in my personal experience, I own at least 9 HW rifles in .22 and they're all up to 1/2" spinners at 50 yards. That includes the 2 little 30s. albeit, it requires a ridiculously big elevation adjustment and a little holdover to boot. I don't profess to have a clue as to why my mileage is different.

When i say Weihrauch 22 barrel efficiency is hit and miss. I wasn't talking about accuracy I was talking about power output.

 

[Pellets&Pistons-(Razor62)]

My apologies. That makes much more sense. Going back and re-reading your post, and I have no clue why I misunderstood what you had clearly stated.
As far as output variation goes, you may be onto something, there. Ive never really given it much thought.

 

[Mycapt65]

My apologies. That makes much more sense. Going back and re-reading your post, and I have no clue why I misunderstood what you had clearly stated.
As far as output variation goes, you may be onto something, there. Ive never really given it much thought.

I unfortunately have plenty experience with it. It's a real thing

 

[JEFFPPC]

I see no results. Not 1 target. Velocity, chrono info......who cares. CAN IT HIT ANYTHING ? Maybe not.

 

[joeayv]

So far not so great… Im going to try again next week. I have a few other projects to work on. I’m probably going to take it apart again and try and size the seal or pop in the old one . Give the barrel a good cleaning. I was able to get one decent group after I through a scope on it. But nothing to write home about

 

[Hateful McNasty]

Use h&n pellets s . Gurrenteed to one hole every pellet under any condition from any gun tin after tin . Thats what im told ..

 

[A.G.R]

So far not so great… Im going to try again next week. I have a few other projects to work on. I’m probably going to take it apart again and try and size the seal or pop in the old one . Give the barrel a good cleaning. I was able to get one decent group after I through a scope on it. But nothing to write home about

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Check your breech seal .. something is not producing constant firing sequence. Piston seal can effect that to if its tight.
1 use thin Kleenex warped over breech and fire. If it’s leaking It will tear. if unsure.
2 shaving Cream will guarantee to show a seal leak. .. self explanatory.

 

[gdc999]

On my Beeman R9 the original seal was "cooked" by improper factory lubrication. I put the Vortek PG4 kit with the Vortek piston seal in and it made a world of difference for me, but did take about 300 shots before I noticed an increase in velocity.
On my .177 R7 I won the lottery! right out of the box it was smooth, no twang, and fabulous accuracy. The best part was it gets better velocity at 1000ft above sea level than the stated factory velocity. I have left it stock (which is very much against my nature )

I agree you need to check your breech seal. A tight piston will lower velocity, but usually doesn't cause erratic velocities.