JSB 22 caliber 25.39 gr accuracy?

I cleaned my barrel last night again to 110%, will go to the range today afternoon. If I don't see improvement in grouping I will just give up the 25.4 MRD's and plink away - like a drunken redneck - some 20 tins I bought the last batch. As for now I am very not happy what JSB is doing lately.

Today I tried all 3 with 960 fps @ 60 yards. Interestingly all 3 the same weight but the pattern is rotating around the X, and, no one groups within in 1".

I never had good accuracy from the Stratons, Jumbo Monsters or even the heavy 34 grain pellets. I’ve only had the best accuracy from the re-designs.

I wash/lube the the pellets and weight sort maybe 3 tins and that was an amount of work I am willing voluntarily to do. I am not going to size check 20 tins for OD or roll sort them.

Anybody have an input if I make a plunge through die and just push all of them through? I don't know the English name for it, would that be swagging?

That would be called a “sizing die”. I’ve used a sizing die to repair damaged skirts but only found those sized pellets useful for practice. 

I never had one or did anything like that, only speculating. Calculating the hours spent for precise sorting with less then 50% success rate maybe better to size them all to same 5.5 mm?

No great accuracy from these, for some reason.

Since mid April I sent about 2K MRD's down a 50 meter range, these are my observation.
about 1" group of 8 shots, anything betweem 920 fps to 960 and ES is extreme wide maybe 20 or about that.
about 1" group of 8 shots but 2-3 flyers 2" away if I tighten the ES to 5 or below.
So a tight Extreme Spread is not my friend. Interestingly a 20 fps +/- from nominal gives me a almost acceptable 1" groups and no flyers.
Always forgetting to mark it up on my rings, the flyer pattern (not a distance)...is it a consistent direction or not. That for next range day I will try to make some notes.

Producing a tight ES spread is generally accomplished by driving the pellet further down the barrel. Essentially using more hammer and consuming more air. It’s not the tight ES that you are fighting…it’s the accompanying muzzle blast. If you are using a moderator….the muzzle blast is now contained around a pellet that is free of the muzzle.

A gun that is setup right with a good barrel will get you a 25 shot group at 50y that is closer to 1/2” ctc with 22 RD monster pellets if you are reading wind and making good holds for the wind.

Mike

I shoot a FX Crown Gen II with FX 25.4 grn pellets at 50 yds here are some groups and chronograph results, 86 shots, AVG 864 fps, Std Dev 5.0.

thomasair said:

....It’s not the tight ES that you are fighting…it’s the accompanying muzzle blast............
Mike

Click to expand...

Thanks Mike, I agree with you absolutely, I am a big fan of airstrippers.
500mm polygonal barrel on Leshiy2, no moderator, 50 meter gunrange - I hate to say it but I could not make the L2 shoot the MDR's to my liking. I am also admitting the L2 is not a friendliest gun to finetune for rings.
I am retiring these JSB pellets for some other gun in the future. For now the AA FT is my favourite for the .22 poly barrel.