.223 Ammo for DCM/CMP ?

[matt]

I've come across statements about cartridges loaded with heavier bullets (80gn) saying only to use them in match chambers specificly designed for them.

That said, I can't find a reference to those statements now...

Any thoughts on this?

 

[Jose]

Matt, your Armalite has a Wylde chamber. It will swallow not only .mil ammo but also any long-loaded 80 grain 600 yard load you can come up with.

You do, however, need to learn to measure your chamber so you can accurately determine the length of your loaded cartridges from the base of the case to the bullet's ogive. There is more to it than can be conveyed in writing here, so seek help from some of the local HP shooters.

 

[bpm990d]

I've come across statements about cartridges loaded with heavier bullets (80gn) saying only to use them in match chambers specificly designed for them.

That said, I can't find a reference to those statements now...

Any thoughts on this?

Sort of, but not really. If you buy loaded ammo with an 80 Gr. Sierra match bullet, it is going to be loaded with a large OAL specifically for single loading in HP competitions. It will probably be much too long for any magazine loading and was probably made so it will fit perfectly in a Wylde chamber. However If you take that round and try and put it into a Remington .223 varmint rifle, it probably wont fit because the varmint rifle has a 1/12 twist and is throated very short to accurately shoot 55gr. varmint bullets.

You can shoot 80s in any of the longer throated chambers like a NATO because you can seat the bullet out to touch the rifling. The problem with a NATO chamber is that your short line ammo that has to be loaded into the magazine ends up jumping a lot to get to the rifling. The big difference with the Wylde is that the diameter of the throat is right at nominal bullet diameter and it supports the shorter bullets when they are jumping into the rifling.

AR-15Barrels.com has a detailed comparison of many popular 5.56 & .223 chambers. Look specifically at freebore length and diameter.

B