Cold barrel point of impact vs warm barrel

H

homesick

New member
I handload for about 8 different rifles all shoot 1 1/4" MOA or better. I have a couple that when I shoot the 1st shot out of a cold barrel their about 3/4" out from next 2 to 4 shots. Example I sight in hunting rifles at 1 1/2 to 2 " high at 100 yds. My 270 FWT will put the 1st shot (cold BBL) at touch to the left 1/4" and about a 1/2" high, the next shots are dead on about 1.5" high.
It seems to be more in the light barreled rifles but not all. I tried to free float my FWT 243 and that was a huge mistake as it went crazy (looked like a shot gun pattern).
Any suggestions?
 
Not to say this is definitely the case, but it may just be you. Try snapping off a few trigger pulls with the rifle empty. It may take you a shot or two to settle in.

That said... I do know where you're coming from. I currently have a custom .308 that hits EXACTLY where I aim it. First time and every time. It's the first rifle I've had that will do that but I'm also more acutely aware of that first shot and do everything necessary to make it a good shot. Next time I'm just plinking I'll try just taking the first shot cold. Without making sure I'm settled and warmed up and see what happens.

I think shooting is like any other sport. You should make sure you're warmed up and ready for that first shot.
 
Yeah, that cold barrel will throw them to a different spot on the target.

I start my hunting season in August, after I work my loads up. Then I start shooting one-shot groups from a cold barrel. One shot only for several weeks until I'm certain that I've got the scope set for that first shot. It's not much of a bother to do that, as I normally take several rifles to the range at one time. For my hunting rifle, it's fire one shot, look at the target, put the rifle in the case. After a half-dozen exercises like that, I know where that first shot is going.
 
A clean barrel may, or may not shoot to a slightly different point of impact than a fouled barrel. The group size will usually be smaller after a few rounds, but the POI should be pretty close. The first 2 or 3 shots from a cold, but fouled barrel should be the same. If not you may bedding issues. After a barrel gets hot, which could take 4-5 shots in fairly rapid fire I'd expect to see some changes.

Wood stocks are much more prone to do this than a quality synthetic.


3/4" is not a huge difference, and probably would not make the difference between a hit or miss. But I'd bet having those rifles properly glass bedded will make them better.
 
I do it about the same as PawPaw.

I’ve been shooting the same loads for years so I don’t do any work ups. I shoot in back of my house so I just take 2 or 3 rifles out, making sure they have been fouled and fire a shot out of each. I then go about doing whatever I have to and later coming back and firing another shot out of each after they've cooled. After three shots if I have a nice cloverleaf pattern for each and it’s necessary, I adjust the point of impact. For hunting it’s always the first shot that counts. Any following shots are an attempt to correct a mistake.

Over the years I’ve found that some rifles open up or move groups when hot and some don’t. I’ve got a .243 that shoots the same hot or cold, but a 30/06 starts to open groups when hot. The hotter it gets the larger the group.

As far as free floating goes, sometimes it works and sometimes it doesn’t. I’ve had rifles that just removing and reinstalling the stock changed the point of impact, some for the better, some for the worse. To shoot repeatable tiny groups you have to do about 73 things the same way each and every time in the proper order......... and have good Ju-Ju too.;)
 
^^X2 what JMR said...
Are the actions bedded, pillars installed?

A cold bore shot from a fouled barrel shouldn't be significantly different than a second shot, in my opinion. Two shots is not enough to heat up the barrel to cause stringing.

POI issues from a cold barrel are often due to receiver movement, which causes the muzzle to be at a different point when the bullet exits with each shot. It doesn't take much...
 
Paw Paw I too start in late Aug. doing the same thing as you / one shot / check POI and put it away. I do this with 2 rifles as I'am a long ways from home. I live in Florida and hunt Minn. or So Dak. I leave nothing to chance.
 
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