Cold Bore Shots from Short Barrel

[ratrod54]

Sitting in a blind in 35 degree weather three weeks ago, I saw a buck I was ready to shoot. I do reload and the load has worked flawlessly. Shooting a 7-08 w/ 18" CF barrer built by Short Action Customs.

I Reload my ammo and have the utmost confidence in the load I've worked up. It has been a very accurate load to date.

I was preparing myself for a 230yd shot. First trigger pull, round is low. Put another round in and did not adjust anything. Second shot, aimed at the same place behind the shoulder and down he went. Never took another step. I questioned myself.

Fast forward to this weekend, my son set up in same blind shooting a 16.5" Barrel Savage PC10 308. Same exact thing. Low first, no adjustment then right on.

Curious, Does a cold chamber and a short length barrel (under 22") have more affect than a longer barrel? Has anyone ever just kept rounds in your pocket to keep them warmer with success and minimal POI shift?

 

[Shane Lindsey]

I have not noticed enough to see a miss at that short a range. I do map my cold/dirty bore and follow up shot. Did you perhaps both have clean barrels that had not been fouled before the hunt?

I tested some powder in my 20" 308 Win a few weeks ago. Freezer and cooler to the range at 34 degrees or so. Fired them and then tested ambient temps at 70 or so. Lost about 1 FPS per degree. At your 230 yards, that isn't enough to show up in my shooting. Maybe by chance your positions in the blind were not quite settled, by the second shot the monopod/rest/forearms, etc. were settled/more sturdy???

There is really only one "cold" bore when the chamber and barrel are at ambient temps so only way to really test is to shoot one and leave it sit until it returns to ambient temps.

 

[waveslayer]

Most likely shooter error, sorry... go test it out and see. Have someone else shoot it too

 

[ratrod54]

I plan to go test it and see. No need to apologize for suggesting shooter error. It happens for sure and I'm not immune.

I do all my load work up at 200 and 300 yards and have found I don't get the fever when shooting at a cull buck. I am positive it wasn't unstable for the shot. I've shot from my BOG at the range and simulated the blind and shoot 3/4 MOA groups. Even a flinch wouldn't have been that drastic.

Both barrels were cleaned a short time ago, but fouled prior to the hunt.

I'm going to wait until it gets cold at home and take ammo from the fridge and see what happens at ambient temps with the rifle.

 

[Rosebud]

Sometimes when you bring the crosshairs down from the top of the back you can push it down to much. I've done it. Get a little excited and don't stop and settle the cross on the spot you want. See it happen many times. Especially if it is a big deer or a long shot.If it doesn't do it on the bench, shooter error.

 

[Bravo 4]

If at 230 yards your first round (cold bore) is off far enough to miss a deer then you have a serious issue with the rifle. I do as Shane said and do a cold bore mapping, that should be the most important round you fire from a hunting rifle. I believe it's as waveslayer stated.

 

[Rosebud]

When you said they were fouled, how many shots were fired to foul them. I've had to fire as many as six to eight rounds to bring some of my rifles back to form. Just looking for a answer to this problem.

 

[ratrod54]

I 100% haven't excluded shooter error. I do not disagree that it's a possibility and contributing factor. That said, it's very hard to prove the state of mind at the time or my ability to shoot. I get that whole heartedly. I do not mean that to sound brazen at all. I fully expect people to draw the conclusion that it's shooter error. I am hoping though that someone has experienced something similar and can understand.

I went back to my original post and see that I didn't not mention both rifles were suppressed. I'm not sure why I left that out of my original post as I believe it is a contributing factor. (I cant seem to edit the original post to include).

18" Barrel had a TBAC Ultra7 suppressor on it and the 16.5" barrel had a TBAC 30BA suppressor on it.

Cold bore shots with a muzzle break have never been an issue. I have had some POI with a suppressor, but not extreme. That said, not had to deal with it from shorter barrels at all so this is why it's caught me off guard.

I would agree that without the suppressor, I would have a massive problem and would blame myself 100% for the cold bore miss. Down to my core, I think there is something else at play here though.

As for fooling, The 7-08 (18") had 50 rounds through it and the 308 (16.5") had between 25 & 30.

 

[Shane Lindsey]

Did you zero it with the suppressor on it to see the shift from suppressed/non-suppressed?

I just shot mine for the first time last night. At first I though it had a larger shift, but after adjusting and fouling the bore more (308 with 152 Hammers), I found it actually only needed about a minute left from the non suppressed. It took it about 12 rounds to foul it up to shoot well though.

 

[ratrod54]

Did you zero it with the suppressor on it to see the shift from suppressed/non-suppressed?

I just shot mine for the first time last night. At first I though it had a larger shift, but after adjusting and fouling the bore more (308 with 152 Hammers), I found it actually only needed about a minute left from the non suppressed. It took it about 12 rounds to foul it up to shoot well though.

Yep! I've been shooting with cans for the last 10 years. I know the POI between suppressed and unsuppressed on these rifles, but I don't shoot unsuppressed at all.

I have had a very small shift from a cold bore shot on my longer rifles (23" and longer). nothing that would affect a hunting scenario though.

I'm going to let it get cold and take four rifles to the range. 16.5", 18", 24" and 26" and see if there's a difference between a cold bore shot and a single follow up from each. I'm going to keep ammo cold as well to make sure it's the same as sitting in a stand in cold weather.

We shall see.

 

[Rosebud]

Keep us posted.

 

[coyote wacker]

I remember several years ago shot a nice buck opening day....just put it on and down it went at the shot....next day a larger buck longer shot missed first shot put it on again and down it went.....
I was confused how could I miss that shot and connect the second....took the rifle to the range next day it was perfect.....
Sometimes we do something while shooting don't remember what and just miss....a complete miss is better than a bad one.....

 

[Mc Fraser]

Some rifles need a couple of rounds after cleaning. Was your rifle cleaned before the shot? I won't eliminate shooter error, but that is for you to determine.
I'll give you an example. I shot a cow elk at 900 yds. A perfect shot died right away. A few weeks later, I completely missed on a moose at 300 yds. I went to the gun range. The rifle shoots 1/3 MOA at 300 yds. To this day, I have no explanation for how I missed that moose.

 

[ratrod54]

I remember several years ago shot a nice buck opening day....just put it on and down it went at the shot....next day a larger buck longer shot missed first shot put it on again and down it went.....
I was confused how could I miss that shot and connect the second....took the rifle to the range next day it was perfect.....
Sometimes we do something while shooting don't remember what and just miss....a complete miss is better than a bad one.....

I've done this before and do not discount shooter error. I really wish this would've been one of those bucks that move the needle but he wasn't. this was a cull buck. Nothing to get the adrenaline moving. Definitely could've still been myself. But I honestly believe this was not me. If I do what I mentioned above and the results show that it was my error, I promise you that I will come back on here and post that it was my error. I have nothing to be upset about if it was me. Just don't think it was here.