What are the recommends for a semi-auto in terms of caliber and bbl heat? Will the commercial AR bbls meltdown if actually used in rapid fire for any duration, say 120 + rapid fire rounds? Any former military armorers out there who know the bbl life of an AR if it is heated up in an extended firefight?

The 5.56 is not particularly a good stopper up close but it seems the caliber of choice for the US.

How soon will a chromed 5.56 bbl foul? Are the SIG and H&K offerings superior or is the price simply inflated?

Thanks.

With semi auto fire, even when pulling the trigger very fast, will get the barrel pretty hot but it will not "melt down". Such shooting lessons barrel life but it's not hard to replace the barrel. I am a "former" (actually retired) military guy who has seen XM16/M16/M16A1/M16A2/A4/M4s fired with a whole lot more than 120 rounds rapid fire in a very short time from 1965 through today.

Given proper ammuntion and at least a 20" barrel the 5.56 does "okay" as a "stopper" up close. My opinion and certainly open for arguement. However I base my opinion on extended and actual use of the cartridge, not just hypothetical imaginations. There are better combat rounds available.

The HK and Sig are inflated by Euro to Dollar conversions. Both are well made but don't give any superior performance to an M16A2/A4.

Larry Gibson

Hey Larry -

Thanks for the reply. I know the heavier bullets in the 5.56 do much better than the earlier spec. And, all the AKs look kinda like battle axes and from what I read here, they are less accurate.

I was thinking also of a Rem pump in the .223 version, of which they currently make 3 models, but only one has a 20"+ bbl. They will accept the AR mags. Fewer moving parts also.

The .223 has less a heat problem since it uses less powder, than say a 308.

And, I thought the SIG and H&K might be overrated.

I just ordered a Rem 700 with the R5 milspec bbl in .308. Curious to see if the rifling reduces fouling. It has the typical HS Sendero stock with the aluminum block.

I have been reluctant to purchase a smaller caliber semiauto as they will not penetrate the higher level armor. I paid for my firearms and if some mutthead tries to take them from me, I want them to "pay".

Thanks for the helpful reply.

As we used to say;

"7.62 NATO, better than Master Card or VISA. Accepted worldwide, never leave home without it!"

Larry Gibson

I've run 500 rounds through my AR with no fouling in the bore. I'll clean and lube the action after each firing session, but basically leave the bore alone.

While the .223 burns less powder than a .308, you can get a .223 plenty hot! Especially when you let your kid shoot them :d