.437” average group size over 18 groups (60 shots)

[rsfrid]

Took my Maverick sniper 25 cal out to range this morning. I just had it gone over by dealer and fine tuned for the 33 grain JSBs at 50 yards. That's all it will be used for — 50 yd benchrest. I like the looks of it with the red furniture.

So, I decided to shoot multiple bulls and average the group sizes (no cherry picking) and this was the result:

I shot sorted pellets and separated by head size. Didn't make much difference with head size. Even with careful sorting, I still had the odd fliers. But overall average was sub moa which has been my overall goal.

 

[JEFFPPC]

Very nice. Now, forget headsize and sort by weight. I would love to see the comparison in a very accurate rifle like yours.

 

[Hard2hurt223]

Nice looking gun and awesome shooting. By the way are you sorting them by weight because I've heard that makes a huge difference also what speed are you shooting because if those pellets are moving above like 850 fps than they will not be stable in flight and can give you good groups but give you many fliers at the same time you might want to do some research on the exact speed for those pellets just to be sure but I know from experience that if pellets are to fast than you will have lots of fliers my 25 cal fx crown gets excellent groups with jsb 25.39 pellets at 912 fps but has lots of fliers but at 880 fps I get great groups with virtually no fliers assuming you are sorting by weight and head size pellet skirts shouldn't matter to much but I would still try to factor that out just my two cents hope it helps.

 

[Ranchibi]

Ross! Gorgeous Mav and what a shooter! Nice pics. Have fun shooting it.

 

[rsfrid]

Nice looking gun and awesome shooting. By the way are you sorting them by weight because I've heard that makes a huge difference also what speed are you shooting because if those pellets are moving above like 850 fps than they will not be stable in flight and can give you good groups but give you many fliers at the same time you might want to do some research on the exact speed for those pellets just to be sure but I know from experience that if pellets are to fast than you will have lots of fliers my 25 cal fx crown gets excellent groups with jsb 25.39 pellets at 912 fps but has lots of fliers but at 880 fps I get great groups with virtually no fliers assuming you are sorting by weight and head size pellet skirts shouldn't matter to much but I would still try to factor that out just my two cents hope it helps.

Sorting by weight and head size both. While head size doesn't seem to matter, I'd bet the groups open up if I don't keep head size together. These were sorted to 33.82-33.90. Not sure of speed right now — think around 900-910fps. It's on 7 on power wheel. I plan to bring chrony next session and lower the power wheel to 6 or 5 and see what happens.

 

[Hard2hurt223]

Sorting by weight and head size both. While head size doesn't seem to matter, I'd bet the groups open up if I don't keep head size together. These were sorted to 33.82-33.90. Not sure of speed right now — think around 900-910fps. It's on 7 on power wheel. I plan to bring chrony next session and lower the power wheel to 6 or 5 and see what happens.

Yeah if that's how fast they are going your going to have instability that is more of a hunting power tune for those pellets it definitely has to be turned down for competition type accuracy. To get the best standard deviations and extreme spreads you will have to adjust the regulator and the internal hammer spring not the power wheel. The PW is only there to give you the ability to change the power on the fly not to give the best accuracy. If you need any tuning advice or help with that process I have a good amount of experience with tuning fx airguns in general and I also own a maverick that I have tuned several times its currently tuned to shoot a 38.5gr nsa slug at 1009 fps and I'm getting sub moa at 100 yds but I've still got some work to do many of the guys on here can give you more info than I ever could and also airarmshuntingsa YouTube channel has a 1 hour tuning video that is very informative. Hope this helps

 

[rsfrid]

Yeah if that's how fast they are going your going to have instability that is more of a hunting power tune for those pellets it definitely has to be turned down for competition type accuracy. To get the best standard deviations and extreme spreads you will have to adjust the regulator and the internal hammer spring not the power wheel. The PW is only there to give you the ability to change the power on the fly not to give the best accuracy. If you need any tuning advice or help with that process I have a good amount of experience with tuning fx airguns in general and I also own a maverick that I have tuned several times its currently tuned to shoot a 38.5gr nsa slug at 1009 fps and I'm getting sub moa at 100 yds but I've still got some work to do many of the guys on here can give you more info than I ever could and also airarmshuntingsa YouTube channel has a 1 hour tuning video that is very informative. Hope this helps

What is your reg set at? Hammer spring is at 4mm I think.

 

[Hard2hurt223]

My second reg is at 164 bar and that is also with the slug power kit.

 

[EPG]

That is great consistent accuracy at 50 yards - nice shooting!

 

[tommyb]

Hey Ross

That’s the way to test for 50 yard BR accuracy! Good representative number of groups and total shots. Newman Buck ( 910 Airguns) told me that he likes to leave the FX Regulators set at near factory levels vs. modifying and playing with them. I sent him my .25 cal Boss ( bought from Mike ) and he tuned it for me a while back. It did like the 33g Heavies at around 875 FPS with the factory reg setting.

I would be ecstatic with .437 sub MOA group size at 50 y in very light outdoor wind conditions with 18 groups. Will be watching you as you lower velocity and see if it gets better.

Nice rifle, like the red.

Tom