CZ 457 build, pre and post bedding results

[BigTex]

If you look at all of the 6x5's the group size from 50 yards to 100 yards usually goes up by a factor of 3, not 2. People who are putting in .5-.6" groups at 100 yards, are putting in .172-.2's at 50 yards.

If you're doing around .37-.4, then you should be expecting about 1.1 - 1.25" at 100 yards. So I don't think it's falling apart, it's just the barrel/shooter. So you should be able to verify if you get a new barrel that if you get down to .25 at 50 yards, then .75 would be generally your 100 yards.

Thanks for the analysis, if you look at the groups I posted here and in the 6x5 thread, you'll see that I have shot several groups at 50yds in the 0.2s, I only have 1-2 groups under an inch at 100yds. Even though 0.1-0.2 is not the average for this gun, it can do it. Sub moa groups at 100 are few and far between, thus my theory.

 

[BigTex]

cherry picked group or two does not make it a gun that does 0.5 at 100

Who are you referring to?

 

[Bantam1]

My 457 is doing a little under an inch at 100 with the Norma that it likes. So far the lot I have has been really good. Maybe I got lucky on my barrel. It's a .22 and there will be variance in the ammo no matter what and we can't control that. I bought it to work on my wind calls at longer ranges as cheaper practice for shooting really long range with my other rifles. It's accurate enough for shooting steel at my local range. There are some smaller swingers at 300 and 400 which make it challenging.

 

[littlepod]

Thanks for the analysis, if you look at the groups I posted here and in the 6x5 thread, you'll see that I have shot several groups at 50yds in the 0.2s, I only have 1-2 groups under an inch at 100yds. Even though 0.1-0.2 is not the average for this gun, it can do it. Sub moa groups at 100 are few and far between, thus my theory.

I'd just look at the averages. I shot a 10 shot 1/2" group at 100 yards with SK Standard +, do I think I'll ever do that again? No. Not even sure what magic beast happened there... I was just doing fouling shots. I then went and did a 6x5, and it averaged around .9" for 6x5. Every once in a while a magic string happens, and again multiply it by 3. So you have a bunch of groups in the .25's (your best on 6x5 is .25) so I'd expect a good amount of groups in the .75, but I know also with me as a shooter, or maybe a bad ES on my ammo, I have groups that go upto 1.5-1.8 if there's that one flyer. It's just so much worse at 100, than at 50. I don't think it's the barrel difference between 50 and 100, it's just the factors of shooter,ammo SD.

I met this person who shot this and can verify.

This is my last outing, when I was ammo testing

My last 3 groups I was getting fatigued, and started ignoring fundamentals. I wasn't shouldering the rifle properly, my NPOA was a bit off...

Anyhow, all moot if you already have a Bartlein coming, I'm curious what it'll do!

 

[*rim-star*]

Bedding a barrel is generaly off no benefit and good smiths generaly avoid it . Full lenght barrel bedding is just bad juju.

I have to agree, although I am aware of stock flex I dont think bedding the barrel is the answer, to many top notch BR guns out there with floated barrels that shoot lights out. I have noticed at least one top BR smith beds about the first 1 inch of the barrel in front of action.

 

[BigTex]

Quick update: I ground out all of the bedding under the barrel, removed the headspace shims and switched to a Bartlein Barrel (glued in). This is the largest improvement so far. 50yd avg 0.277", 100yd avg 0.879"

 

[Tomiboy]

Was that with the can in place?

 

[BigTex]

Was that with the can in place?

Yes, new can. Rugged Oculus.

 

[Tomiboy]

Have you tried for groups without the can. My rifles shoots more accurately without my TBAC TD22 can

 

[BigTex]

Have you tried for groups without the can. My rifles shoots more accurately without my TBAC TD22 can

This one shoots about the same with/without the Oculus. Not the case for the YHM Mite I had on it before.