RX2 problem

Jump to latest Follow Reply
josh3rd

josh3rd

Member
Apr 2, 2015
954
49
Newark, Delaware, United States
As some of you may already know, I have a Beeman RX2 in .20cal. Not to long ago I let out a bit too much air from Beeman's spec's (which is I believe almost full pressurization), which is too much in my opinion. So anyway I tapped the valve twice to let out some air and obviously it's speed/power reduced also. Now that was an issue for me but for the time being I am content with it. I don't have a chrony but my guess is that it's above 12ft/lbs and below 17ft/lbs., which is fine w/me.

Okay, now here is my issue. I had a optically centered Simmons Pro Mag 6-21x (I believe) on it with a BKL one piece mount. Then I bent the barrel for the POI to hit about within a 1/2" of a target @ 25yds. The way I bent the barrel was via NCed's way with an eye hook and nut. It grouped nice and then it started to chance POI from the same POA. I thought it was my hold so I concentrated and the POI was still changing...mostly vertical with just a little movement to the left, about a 1/2". So I changed the mounts to a UTG 2 piece mount. Same thing occurred. I sighted it in @ 25yds and then the next 5-10 shots my POI began moving again as it did with the 1 piece mount.

I got a replacement scope from Bushnell called the Engage 4-12x 40mm with the MOA reticle. Mounted it in the BKL 1 piece mount and then the UTG 2 piece mount onto the RX2 and the same situation happened as it did with the Simmons earlier. So that tells me its not the scope.

So I did the tissue test over the breach lock up area. Fired 3 shots w/o the tissue moving what so ever. I made sure that all screws on mounts and stock were tight. Same issue. Now from my experience w/springers there can only be 2 other things that can/are affecting my rifle. 1 is the piston seal and the 2nd thing could be the RAM. Do you guys/gals have an idea, opinion or answer to my dilemma? Oh yeah, when I cock it, the barrel stays where I leave it before returning it to battery. I tried to untighten it but man, whoever had it before me must of really cranked it down because I wasn't able to loosen it. And lastly, do you think it could of been my "tweaking" of the barrel?

1) I checked all screws
2) I concentrated and repeated my hold
3) I tried different scopes
4) I tried different mounts 
5) I checked the breach via tissue test
 
You might try scrubbing the hell out of the barrel, especially the breech end. I had an RX2 .20 that was extremely accurate over the course of months or more. One day I was plinking and having a great time and suddenly couldn't hit a thing. Velocity was exactly right and single digit ES. Checked stock screws etc. Every thing was great. I never solved it and sold it..... regrettably. 

Fast forward a bit and a friend had a Theoben .20 that started behaving similarly. We went through all the same process with similar results. THEN I ran across a thread about that same problem with Whiscomb rifles. Turns out that the combustion of the oil products in high power springers would build up at the breech to the point that it would size the pellet too much and accuracy would suddenly go away. On Whiscomb JW80s, that meant you had to clean every 50 to 100 shots. Not as bad for Rx's but still a problem. John Whiscomb developed a lube that wouldn't combust in his springers and would extend the cleaning interval. I forget the formula but if it interests you, do a search for Whiscomb lube. 

Hope this may help. 

Bob 
 
Upvote 0
 With the barrel closed tap the end of the barrel and see if moves at the breech end, if there is movement the barrel is not locking up tightly. This will string your shots. If this isn’t the problem I would replace the piston seal. Pity you don’t have a crony to test the ram but another way is to test the consistency of the ram by placing it in a press to test the amount of weight it takes to start compression. It should be the same for each compression. Also what Bob said clean the barrel, that’s the first thing I do when accuracy starts to wander

Good luck,

Gary 
 
Upvote 0
You must log in or register to reply here.
Top Bottom
Back
Home
Forums
Resources
Menu