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Posted: 1/8/2009 7:43:05 PM EDT
| I am aware that the maximum length for .223 Rem cases is 1.76 inches.and the standard trim to length is 1.75 inches. But, does this hold true for rifles chambered in 5.56 or do you have more leeway in the maximum length allowed? |
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Quoted:
But, does this hold true for rifles chambered in 5.56 or do you have more leeway in the maximum length allowed? There is QUITE a bit of leeway allowable in case lengths. I don't think that it is unique to 5.56 chambers though. There are quite a lot of aftermarket barrels marked 5.56 that are not in fact 5.56 in dimension. Let's take Black Hills Blue box ammo as an example. Gazillions of rounds of this stuff have been shot by all kinds of aftermarket rifles with God knows what array of chamber variances. You never hear a negative thing about BH Blue box right? That brass is about as far out of length spec as you can get. That stuff is CRAZY long. My guess is that there are no issues with BH blue box ammo due to the fact that it's .223 pressure/velocity ammo. 
Are you asking if trimming cases is necessary? I never do it. I run a Lee Factory crimp die however. If my brass gets half as out of spec as Blue Box, then I throw it in the recycle can. There's a handful of folks who will tell you that not trimming your brass to load .223 will make your gun blow up and all kinds of nonsense. The ACTUAL FACTS, however, contradict that myth. Now if you're trying to get full power loads out of your gun, you might make sure every spec in the load is met. |
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Are you asking if trimming cases is necessary? I never do it.
How many AR's and/bolt guns do you load for? One should be safe and trim cases below 1.760. It is the M193, M855 MilSpec max. length. Chamber reamers do wear. Case necks do grow when sizing. When the shoulder of the casing contacts the mating shoulder in the chamber, the end of the casing should have some clearance between it and the mating step in the chamber leade. You may not crimp into cannelures either. If the crimp in the neck down into the cannelure ends up being trapped by a shoulder in the chamber, bad things can happen. I did not know Black Hills did not control their casing length. I will never buy any Black Hills. Thanks. |
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Quoted:
I did not know Black Hills did not control their casing length. I will never buy any Black Hills. Thanks. This is unique to the Blue Box REMAN ammo... or at least that's the only ammo I've checked. I would shoot it. It's good ammo. But since I don't trim cases, I can't use the brass for reloading. This makes the Blue Box less attractive for me. The point is that BH Blue box is way long in the brass and I've never read about a single problem related to that ammo. So if BH can get away with grossly over length cases, the average .223 reloader is probably safe loading slightly long cases. Also, the bigger part of case neck growth is when the expander ball is pulled back out of the brass, not the resizing. (thanks to We-Rborg for teaching me that) As my expander ball has worn out, I've noticed almost NO GROWTH in my brass when resized. I don't understand what you mean by not crimping into cannalures. I do it all the time. Military ammo is crimped, and the crimp is always in the cannalure. |
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