Advanced Marksmanship heat effecting shots?

[Graywolf.260]

Re: heat effecting shots?

I'd like to understand why you say (any) rifle barrel that exhibits degraded performance on heating isn't acceptable. I understand the point, if you are talking about a specific class of range rifle that will be used hard. But what about a sporter barrel in a "high quality" hunting rifle. E.g., Sako 85s are usually capable of well below moa accuracy but in my experience, don't overheat the barrel or accuracy suffers. If lightweight sporter barrels could be regularly turned out that were unaffected by heat, then why don't more tactical rifles have sporter barrels, or put another way what is the point of a heavy barrel? Again, I'm asking because I really don't understand, not being sarcastic.

 

[jeech]

Re: heat effecting shots?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Sterling Shooter</div><div class="ubbcode-body">I've had a few factory sporter rifles which apparently warped as they heated up, therefore, precluding me from being able to come to an understanding about where the barrel was pointed. I have often wondered why those barrels warped as they heated up. But, beyond wonder, being unacceptable, I returned both of the rifles under warrenty, for replacement.
</div></div>

Hey guys, sorry to bring back a touchy subject, but I had a question about this comment. How can a beginner shooter like myself tell when it is a bad barrel and when it is just poor, unrefined marksmanship skills? (the latter I suspect would be the case if I encountered this)

 

[Goldbeachman]

Re: heat effecting shots?

How about go shooting with someone who is a confirmed competent shooter and have him or her shoot your gun to a statistically relevant level and then you do the same (preferably on the same outing/same conditions). That should tend to rule out shooter vs. gun/barrel.

 

[Greg Langelius *]

Re: heat effecting shots?

Having missed this thread, then reading it through in its entirety; I am particularly struck by the missed opportunities for learning which have become obscured by ego excursions.

Does heat affect accuracy? It does for me. Can't say why precisely, but I suspect that propellents are getting heated and that temperature does have some sort of an effect on barrel harmonics. I think this affects both the load's bore transit time, and the ideal transit time for the given barrel. If one doubts me, try shooting 20 rounds of .22-250 in 5 minutes.

Pressure points and Rem 700 .223's. Yep I got me one of them too, a VLS. While it could be expected to find one on a sporter weight barrel, I was mildly perplexed to find one on my VLS too. Well, hell; that can't be right, right? So I removed it. Wowee, big mistake.

I think pressure points are a stopgap fix for more complex issues. I think that a heavier barrel shows similar heating/inaccuracy responses to a lighter one, and being a more effective heat sink, takes longer to return to 'normal' (whatever that is) when cool.

A heavier barrel does not handle fast shooting cadences better, it just takes longer to get bad, and longer to get better afterward. I don't think a pressure point improves on this. It just complicates it.

If I had to say something definitive here, it would be the following. Once you've shot too fast and overheated the barrel, fewer good things happen to accuracy, more bad things do, and it usually won't cool down again in time to finish a competitive string of fire accurately. Moral: start slow, use all the time allotted, and it's better to start too slow and need to hurry later, than to hurry sooner and realize you've just put yourself too far behind the 8-ball to came back with anything resembling a decent game.

I'm a Marine too. I know LL, and just off the record, being a Marine is one of the more minor of his professional shooting accomplishments. Speaking for myself, being a Marine also tends to get my mouth going a tad faster/further than might be ideal. I have no idea whether LL shares this shortcoming, and I'm not really all that interested in finding out, either. Him bein' Head Honcho here, and all...

Greg

 

[SaepeExertus]

Re: heat effecting shots?

Haven't read the whole thread but in short yes as your barrel heats up your point of impact will shift. Since you are shooting a 270 I'm assuming it is a hunting rifle and doesn't have a heavy barrel? You're going to see more of an affect on your impacts with a smaller contour barrel then you will with a rifle with a larger contour. It's just a matter of the powder burning faster at a higher temperature. Try keeping your rounds covered out of of direct sunlight when not in the rifle.