I've got a .22 high-powered springer that I've been shooting for 1.5 years and really like it but I want to add a gas gun to my gunsafe. After MANY, MANY hours on this forum as well as others, I think I've come up with a plan. The QB or AR seems to be the best start, as it seems the equivalent of the small block Chevy: cheap, reliable, easy to work on and parts are easy to find. This would be a .22 used for some informal target shooting and hunting at 20-75 yards. I have a home machine shop at my disposal. I am not a" pro" machinist but do have considerable creativity, visiion and determination. Here are my goals for the end result.
1. Be very accurate. 1" groups at 50 yards would be acceptable. Consistant velocity seems to factor in here, especially when shooting past 50 yards, which I do a lot.
2. Have good power. A 14.3g pellet at 850fps+ is the goal.
3. Have a long shot count. At LEAST 100 full power shots before refilling. Preferrably 200 or more shots would be desireable.
4. Be reliable.
5. Reasonable cost (not have to sell a kidney to finance the project).
6. Be reasonably easy to work on and get replacement/upgrade parts.
7. Look similar to goodgroup's modified QB
http://www.gatewaytoairguns.com/airguns/forums/thread-view.asp?tid=16652&mid=135173#M135173Before I commit and start purchasing, there are some questions I have. If anyone knows the answer(s), please chime in.
1. What are the differences between the QB and AR series rifles? I understand that the QB78 & QB79 are the same rifle except for how the CO2 is provided. It looks like the AR2078 is a restocked QB78 with fancy sights and an AR2079 is a restocked QB79 with fancy sights.
2. Is any one of these a more accurate rifle in general? Do the AR rifles have a better barrel?
3. How hard is the gas block to remove? I'll be converting this gun to HPA and probably run a 47 cu.in. tank with a 1100# regulator on it so it will require a custom "dropped" gas block. The 47" tank is 3" in diameter so a 5/8" drop should work. The 13 & 22cu.in. tanks are about 2" in diameter.
4. Has anyone used the JRA? multi-shot breech with the rotary magazines?
5. Can the gas tube be shortened? I'm wanting to get the larger air cylinder as back as far as possible. I'm thinking of cutting the tube shorter, leaving just enough length ahead of the front of the valve to mount the drop-gas-block.
6. If you run 1100# HPA in this valve, will I have to do work on the valve or replace parts to achieve the desired power? I see that goodgroup runs a RFM valve and gets the power I'm looking for. Is this necessary?
7. I haven't seem much on power adjusters. Can one be fabricated for this gun?
8. How good (or bad) is the stock trigger? I'm thinking of reworking the trigger with custom parts.
9. Is the safety a pain to use? It looks like you have to rotate the safety lever to engage/disengage the safety. I'm thinking of a lever type in front of the trigger like my TF-89.
10. How difficult is loading this rifle with a scope on it? I'm wanting to use a Leapers Bug Buster 3-9X32 scope. Will a compact one-piece mount work or will it need to be 2-piece mounts?
11. I plan to use an AR2078 stock and modify it to accept the air tank and lengthen the LOP.
12. Is there anything I'm overlooking?
Thanks to "ribbonstone" and "goodgroup" for sharing their custom guns.
Thanks for any info.
Doug