Raptor review/ongoing thoughts

Update

I had a little time between review rifles and got more adventurous with the extra barrels. The C707 barrel seems promising with NSA slugs. Prelim testing suggested that it can keep them under an inch at 55 yards at 50fpe. 

It was set up with that Career barrel a few days before the FT match last weekend when I got a wild hair to shoot it at the match.....at midnight, two nights before I was planning on heading to the match. So, out to the garage. Took 5 or 10 minutes to do the caliber swap and another 20 or so in front of the chronograph to get it to a 20fpe .20 cal gun. I wasn't liking that the hammer spring adjust was only hanging on by 1 or 2 threads so cut down a long and even thinner wired spring. That is the third step-down in spring wire diameter from the hammer spring it came with. So, new spring and power adjust in about 6 full revolutions + some tinkering with the striker length got me a pretty consistent 19.5fpe. A spread of about 30fps is really about the tightest the gun can do at 20fpe. I think the balanced valve is just more appropriate for higher fpe. 

When I had pulled the Daystate barrel, I left the shroud and endcaps all assembled and was thinking I could shoot it at 20fpe in .20 at the match with just the bare barrel, no shroud. During practice the day before the match, I found the barrel could wiggle a little without the shroud holding everything tight, so stole the shroud off the Daystate barrel/shroud assembly (thinking it'd be nice to have an extra piece of tubing/shroud to leave that one assembled). 

Worked out all my distances and impact points and was feeling pretty confident with it, thinking I was semi-prepared for competition. 

During the match I had some really low-impacting pellets. On one of the longer shots I saw the pellet hit the ground in front of the target. I also saw some pellets hitting inches low on the face plate. Finished with a 33/52, not knowing what the problem was, but knowing I had a serious one somewhere. 

A few days ago I had a chance to do some troubleshooting with the chronograph. I'd left all the settings the same, to aid in diagnosis. First ten shots had a spread of 63fps, five more shots made the spread for 15 shots 103fps. Okay, there's at least part of the problem, but why? Sat there and thought about it for a few minutes, getting more angry. Texted a buddy and he had the thought that maybe the balanced valve was acting up. I was wondering if the hammer spring was hanging up or binding. We had talked about cutting a groove into the thimble for a small oring and I was also considering constricting the tport through the thimble, because of Motorheads reports that the balanced valves responded well to small tps at low power output. 

So, next step, pull the thimble for inspection. The thimble can come out the breech cutout where pellets are loaded, while leaving the barrel in the breech, so that's what I did. During inspection I realized that the probe oring groove was missing something important.......an oring. A HA!!!!! At that point I remembered that I started having sporadic rough feeding issues during the ft practicing and during the match. What was happening was that if the cocking lever was closed slowly, the head of the pellet would tip into that oring groove and get gouged. I put the thimble back in and tested this theory and......big hunk taken out of the pellet head. So that further explains the mysterious what the heck shots I was having. I got a oring back in there and MUCH easier feeding, and accuracy returned. Back to pellet on pellet. 

So, the problem appears to have been as simple as a missing oring in the groove cut into the thimble to seal the pellet probe. Doh.

I decided to see if it would be possible to tune for a smaller ES than the 30 that I've typically seen in the various instances when the gun has been a 20fpe critter. Nope, not possible. The best I could do was a 27.4ES over 30 shots, so that's where it is now. 

I've got a new review gun so it might be some time before any further Raptor tinkering, although I'm considering using it for the 20fpe silhouette match at the Southwest Airgunners July shoot. 

Some other tidbits of info I learned about the gun in the past few weeks:

166 shots from 2900-1600fps (20fpe with .20 and lots of adjusting of hammer spring/striker during this 166 shots-reg pressure is between 1000 and 1100 and bottle can be filled to 4350 so lots more shots above 2900 and less than 1600fps)

I bought a digital trigger pull gauge and 10 shot average trigger weight with the Raptor = 0lb 3.9oz. Lighter than I thought it was and actually lighter than my USFT. The USFT averaged out to 0lb 6oz and the Veteran trigger averaged 0lb, 5.6oz. Although both the Raptor and the Veteran have lighter triggers than the USFT, they don't feel as good/not as smooth. That being said, all three of these guns (Raptor/Veteran/USFT) have really good triggers. This second gen Raptor trigger is actually a much better trigger than I expected when I ordered the gun. 

I was also curious about the claimed reduced cocking effort from the balanced valve, so used the same trigger pull gauge to test cocking effort. 5 shot average cocking effort with the Raptor in it's current 20fpe tune = 2lb 15.9oz so basically 3lbs effort to cock the gun. That then made me curious about cocking effort on other guns. The most comparable would be the Taipan Veteran, it is also set for 20fpe but in .22 right now. 5 shot average cocking effort for the Vet = 6lb, 9.1oz. So, balanced valve reduction of cocking effort is most definitely accurate, as it is more than 1/2 the cocking effort of a comparable side-lever gun at the same fpe output. 

Going from 50fpe to 20fpe was also my first experience adjusting the regulator (machinist buddy had done it prior). Man is that an easy adjustment to make! Simply turn it and watch the reg pressure come down. Sweet. 

Hammer springs

Another AGN member and I had a discussion today about hammer springs. I suspect that JSAR sent out various strengths of hammer springs. 

Wanted to post this in case it can help someone...



Bottom is what came with my gun from JSAR. Wire diameter = 0.055 inches. Haven't found a use for this one yet. Guessing it'll do something like 60-80fpe in .22 with slugs.

Middle is one I sourced at ACE and wire diameter = 0.047inches. This spring will do 50fpe in.22 EASY(not much compression of hammer spring tension required for 49fpe).

Top is also one I sourced at ACE. Actually, it's the other half of the one that is currently in the gun. Wire diameter on this one = 0.041 inches. It's doing 19.5fpe with th .20 barrel and there's still a lot of compression available imth hammer spring adjuster so it'll likely do more fpe easily. 

Inner diameter of all three is about 0.4 inches (average).

Outer diameter is roughly 0.5 inches (average). 

You can count the coils in the pic. 

Field Target Revisited

Motorhead's recent reports of how he did with his Raptor at the Oregon Grand Prix reminded me of some recent testing I did with mine.

Two weekends ago, at the Aspen Mtn FT match in Western NM, I had the chance to shoot through the course with the Raptor after the official match. 

https://www.airgunnation.com/topic/southwest-airgunners-aspen-mtn-july-match-report/

It was a 52 shot match, and not an easy one. 

I decided to shoot through with the Raptor afterwards, using the known distances. The reason for that was that I was wanting an assessment of the gun's ability to shoot accurately. The idea was that I could remove the variable of ranging error and get a better view of the Raptor's capabilities. 

The Raptor shot a 46/52, a better score than I had for the official match. The misses were my fault, yanked triggers, unsteady, etc. I was quite pleased with that score of a 46, as the course was pretty tough. 

To recap, that 88.5% knockdown was shot with a .20 LW barrel, using the JSB 13.73gr at about 800fps. I understand Motorhead's Raptor Mini FT has a different valve, but mine still has JSARs balanced valve. I've had the gun up to 50fpe with a .22 barrel so that valve has quite a range of power output. I feel like more power wouldnt be hard to achieve. The trade-off to that wide range of power is that the ES is not the greatest on the low end, living around 25-30fps when the gun is doing 20fpe. Good enough for FT, depending on who you're asking. 

Miscellaneous Raptor Musings

This past weekend we had another FT match just south of Flagstaff, and while I didn't compete or shoot through the course with the Raptor, I did get it out for the plinking fun after the match. 

We'd set some paintballs out around 45-55 yards and the first shot after getting the Raptor out was dead center, SPLAT on a paintball at about 50 yards. That is a good thing, considering how important it is for a FT gun to hold it's zero and be repeatable and dependable. At that point, the gun had been packed and hauled from Luna, NM, to my house, to Flagstaff, AZ in two different trips and multiple ins and outs of gun cases, gun cabinet, and vehicles. 

After the paintball popping fun, I moved out to the bell target set out at 116 yards. I think the KZ was about 2 inches. Once I figured out the dope and holdover, I was able to ding that bell about 80% of the time. Pretty good for 20fpe at 116 yards in some unfriendly winds.

So, still shooting and enjoying the Raptor. Lots to like. 

Alright, going back to .22 high power but first wanted to see how my 20fpe, .20 tune held up.....

20 shots over the chrono: high 813.2, low 782 and average -801. 

That's right where it should be, keeping the same 30fps ES that is about the tightest the balanced valve can do at these low powers. Right where it was the last time I shot it over the chrono. Nice. 

Going to the .22 barrel now. 

I'd gotten the gun rough tuned to around 50fpe with the .22 barrel about a week ago, and just had a chance for a pretty decent tuning session with the chronograph. 

I initially wasn't liking my ES and how the gun was acting and sounding. I tried all three of the aforementioned springs and various reg pressures. Ultimately I ended up with the thinnest wire spring (0.041inch wire diameter, 2.5 inches long, about 12 coils and roughly same diameter as the spring the gun came with). Hammer tension is 6 complete revolutions in from the hammer tension nut being completely out of the gun. Striker is 4 turns out from completely bottomed out ("out" being counter clockwise). Regulator pressure is now at 2000psi. Other than the regulator pressure, the hammer tension and striker settings are really close to what I had with the 19.5fpe .20 tune and I'm actually using the same spring as the 19.5fpe tune now. 

Following string was shot from 3200-2100psi.



 

So that puts me right around 52fpe. The goal was 960fps with the JSB Monster Redesigns, and I'd say I'm pretty well there, looking at my average. 

There should be some good shots with a higher fill pressure so should get a higher shot count than represented above. Overall it has a noticeable (and slightly worrisome) descending trend. I'm kind of tired of tinkering with it at this point though, and just want to shoot it and see how it does so I'll see what kind of accuracy results this provides before any further tuning. 

Really interesting to play with all the ranges of the tuning adjustments. All the various tuning philosophies can be employed with this gun. Short stroke/heavy hammer hit, long stroke/light hammer hit and all the variations in between. The gun and valve sure tells ya what it doesn't like though. If it's way out of wack it'll do that hammer bounce barraaatttt thing I've mentioned before. If it's a little out of balance, it'll have a loud and slightly prolonged report. If it's just right it has a very quiet, short, and crisp report. The above chrono numbers are producing that really quiet crisp report and overall docile effect. So, it SEEMS pretty well tuned. 

After I finally got it to this point, and realizing how close it was to the same settings as the sub 20fpe tune with .20 (only variation being a reg pressure of about 1100 with that tune), thought to myself, how cool would it be to not have to mess with all these hammer tension and striker settings and just be able to use the regulator adjustment to go back and forth between 20fpe/.20 and 52fpe/.22. So, I tried to run the reg back down to 1100 psi and it now won't go down that low. It bottoms out at 1500psi. I tried some .22 pellets in 13.43grain (the closest approximation to the .20, 13.73gr without actually swapping the barrels) at that 1500reg setting and they're going 1050-1060fps. So, it seems that I'm stuck at this higher power for the time being, which I suppose is fine since that's what I'm wanting to shoot it at right now. BUT, in order for me to ever get back down to 20fpe in .20 for field target work, I'm going to have to figure out why the adjustable regulator will no longer go as low as it did before. Out of curiosity I also tried to see how high the reg would go and its 2500psi, which is about where it was before. Really curious to know why it will no longer go below 1500psi and will absolutely have to chase that down when the gun goes back down to its field target setting. 

Anyway, accuracy testing in HP configuration to follow. I've got some of Centercut's EBR challenge in mind with all this reconfiguring.