TEC said:
TeamRush:
Thanks, that makes good sense. The ammo I am buy in bulk is the UMC 55 gr metal case .223 Rem. I don't hand load, and I will primarily be punching paper, but not competitively, as well as plinking and occasional varmint shooting.
So it sounds like the CZ 527 Varmint Laminate w/ 1:12 in twist will indeed serve just fine. And if I understand correctly, it is better to under-spin the occasional heavier round I might be shooting and sacrifice a bit of accuracy in that situation than it is to consistently over-spin the light, copper jacketed 55 gr rounds that will be the bulk of my shooting, both sacrificing some potential accuracy and tending to more quickly foul the barrel with build up from the metal jackets. Correct?
My 1 turn in 12" barrels ALL like about anything under 65 grains...
You go over 65 or 69 grains, you will start to see the accuracy suffer,
But all in all, anywhere between 40 grains and 55 grains the 1-12" is just GREAT for plinking and with the 'Right' ammo, will do MOA accuracy with ease.
I have a good friend with CZ .223 rifle, and it's probably more accurate than the .223 Ruger I like to shoot most.
Very nice rifle, well made, accurate, and LOVES the cheap factory ammo!
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I want to give you a word of warning about using military surplus 5.56x45mm NATO ammo in your CZ bolt rifle...
Military 5.56 is 'Hotter' than .223 Remington ammo,
And no matter what the 'Experts' tell you,
Military/NATO 5.56 IS NOT .223 Remington!
Different tolerances, different case, different muzzle velocities, different bullets...
Military ammo uses 'Hotter' powder, meaning the chamber pressure is going to be higher than the 'Hottest' SAAMI recommended load.
http://www.saami.org/
Military ammo uses a different neck length to the case than .223 Remington. It's slight, but can create freebore problems.
Military ammo uses much harder copper alloy on the jackets,
Especially foreign import ammo which is VERY HARD, and can work over your rifling very quickly.
Since you have a VERY nice rifle that is also Accurate from the factory, I just thought I'd bring that to your attention.
You probably won't have any chamber failures or barrel failures,
But excessive chamber pressures CAN oversize the chamber, expand the barrel throat, ball powders especially will erode the barrel throat,
And you might have bolt operation and ejection problems from the greater than designed for chamber pressures.
Not trying to scare you, since I don't think the rifle will 'FAIL'...
I just think that shooting military surplus or those imported rounds are hard on any finely made rifle!
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Remember, the most important thing is barrel break-in to accuracy!
Don't worry about what you have been told by 'Experts'...
Clean the crap out of what ever barrel you have, no matter how old,
I often plug one end, and fill the ENTIRE barrel, chamber to muzzle, with copper solvent and let it stand overnight...
You won't BELIEVE the crap that comes out of some barrels!
Then clean it REALLY WELL everyday for a week or so,
Until you stop getting 'Green' on the patches when you use ammonia based copper cleaners...
(and remember, it often takes an hour or more for the 'Green' or 'Blue' to show up on patches!
You aren't just going to push them through and get 'Green' right away!)
Clean the CRAP out of that barrel,
Then fire ONE shot,
Clean the crap out of it again,
Fire ONE shot,
Clean the crap out of it again,
Fire ONE shot....
Repeat about 10 or 20 times...
What you are doing is 'Burnishing' the barrel.
When you machine a barrel, it gets all kinds of scratches, nicks, chatter marks from the cutting tools, ect.
Copper (or in some cases, Lead) collects in those low spots and works like a 'Hydraulic' medium, protecting the gouge or scratch, while keeping the rest of the barrel metal from 'Smearing' into the edges and filling the holes up.
If you properly 'Fire/Clean/Fire/Clean' the barrel,
The edges of those scratches will soften and round over, and not gouge up the bullet as much.
With new barrels, it's CRITICAL to break in the barrel by firing/cleaning it.
The 'burrs' and gouges on the edges of the rifling will cause problems.
Burrs imbed in the bullet, then scratch the barrel all the way out.
Gouges and chatter marks will first de-breed of sharp edges as they brake off in the soft copper jackets, and do harm to the barrel,
Then the gouges will take 'Bites' out of the bullets after there are no more burrs or chips to send down the barrel.
Great cleaning will carry off many of the larger, looser chips and burrs,
And fire/clean will get the rest out with Minimum damage.
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If the barrel has already been used (as in used rifle),
You can still clean out ALL the copper/lead,
Then follow barrel break-in procedures (shoot/clean/shoot/clean) and that will help 'Burnish' and wear down the 'Hydraulic' pockets of copper... And actually wear down (Smear) the metal edges and fill in some of the low spots/chatter marks/scratches, ect.
Shoot/clean about 10 or 20 rounds,
Then shoot 2 rounds, clean, shoot 2 more rounds, clean, ect for about another 20 or so rounds...
You will find at the end of the 'Break-In' procedure you can get the barrel clean with one brushing and about three or four patches!
I don't know about you, but the easier cleaning through out the life of the rifle is worth a day breaking in a barrel for me!
Not to mention I have NEVER seen a barrel that didn't get more accurate, no matter how old the firearm...
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There are some 'Fire Lapping' kits out there,
Where you introduce an abrasive to the bullets to 'Scrub' or 'Sand' away stuff in the barrel...
DO NOT USE THOSE!
You can REALLY screw a barrel up with those fire lapping kits if you don't know EXACTLY what you are doing!
Fire lapping *CAN* make your rifle more accurate...
*IF* you have VERY SPECIFIC problems!
Most of the time, they just oversize the bore, and wear down the rifling to a point the barrel is useless!