battle/assault rifles; which ones maintain accuracy when hot?

[MyRoad]

Any guns accuracy will be effected by heat. Does anyone know which battle rifle or assault rifle can best maintain its accuracy when hot? I prefer semi-autos in this realm, but I'm open to bolts if that makes a difference.

I'm not thinking about taking out an army of zombies, just about being able to spend an afternoon at the range doing various types of target practice, without having to think about cooling down the barrel so much. Granted, I like to take breaks periodically, but I'd rather do it because I feel like it, not because the gun can't hold a group anymore.

I'm asking about battle and assault rifles because it would appear they are designed for 'sustained fire', but obviously if I'm looking for target work, I'm looking for something that leans towards better accuracy. What makes it fun for me is making every shot count, and trying to perfect the run. I am NOT emptying 30 round magazines as fast as I can! But I might shoot a couple of hundred rounds in an afternoon. I would say 2" @ 100 yards cold, and optimally no more than 4" hot, would fit my expectations. Is that too much to ask?

 

[Correia]

The one group of shooters out there best able to answer your question are 3gunners. It is a competition that balances speed and accuracy. We will often dump 4-5 aimed shots a second, and then have to slow down to pop 200-300 yard targets.

The vast majority of us shoot an AR of some type. Barrel length and weights vary from shooter to shooter. A few of us shoot something else.

 

[ocabj]

You want an AR. Service rifle upper would be best (ie: 20" 1-7" twist SS barrel).

Since the course of fire for an Across the Course match is:

Standing, 200 yds., slow-fire (10 shots in 10 minutes)
Sitting or kneeling, 200 yds., rapid-fire (10 shots in 60 seconds)
Prone, 300 yds., rapid-fire (10 shots in 70 seconds)
Prone, slow-fire, (20 shots in 20 minutes)

These rifles will hold up to a good amount of shooting and still maintain accuracy.

A 16" heavy chrome lined will probably be accurate enough for you, though.

 

[MyRoad]

Service rifle upper would be best (ie: 20" 1-7" twist SS barrel)

Do stainless steel barrels hold true when hot better than non-stainless?

What about chrome lining?

 

[ocabj]

I'm not a barrel expert, but Krieger states there's no difference in accuracy between a chrome moly and a stainless steel barrel.

 

[MyRoad]

So what is the advantage of stainless?

 

[ocabj]

Some will say SS lasts longer than chrome moly, but barrel life typically is the same.

SS is softer steel and is easier to cut. Therefore, it is easier to make a match barrel from SS. That's why most match barrels are SS. If you see a barrel sold as "match grade", it's most likely SS. Pretty much all the high quality barrels you see by Krieger, Lothar Walther, Broughton, Schnieder, etc, are SS.