Cold bore shot vs. rest of group

[streetstang67]

I'm sighting-in my rifle (remington 700 sps, .30-06) and getting different placement for my first shot(s). After the first shot or two, the groups begin to stabilize and I can zero my scope. The problem is, when I go hunting, I wont have a couple shots to take before getting a stable group, only the first (cold bore) shot will matter.

First off, is this normal?

And second, does this mean that in order to hit bullseye with my first shot, I have to let the gun COMPLETELY cool down after each shot when sighting-in?

 

[v8stang289]

I have a remington 700 in .270 and my gun acts similiar to yours.
The first few shots are sort of erratic and dont group very well, but after the first few shots it begins to group more consistantly. However the point of impact is not greatly changed, all of the bullets hit within a small area. Its close enough that i have never had a problem when hunting.

I think its pretty normal though. I have a friend that target shoots with a 700pss in .308, and he always fires a few shots to "foul" the barrel before shooting groups.

-matt

 

[jerkface11]

It probably isn't due to the bore being cold. It's more likely because the bore is clean. Don't clean it after your next range trip. It should be consistent on the trip after that. And don't believe anyone who tells you that it needs cleaned after every 20 rounds either. I don't clean mine till the accuracy drops off.

 

[taliv]

my rem700 vss in 308 would print different with a clean, cold first shot. however, it would always put it in the same spot. about 1/2" low and left.

 

[KINGMAX]

Consider a fouling shot after cleaning

If you are cleaning your rifle after each trip to the range, you may want to consider shooting a fouling shot.

Some hunters won't clean their rifles after they complete scope work for a hunting trip or even season.

I shoot a cold shot to see where my first shot will normally hit.

 

[IndianaBoy]

I stopped cleaning my rifle until I was ready to start shooting another batch of handloads.

If you clean all the copper and fouling out of the bore that you put into it when you zeroed the scope, it will shoot differently until you lay down another layer of copper and fouling.

 

[DoubleTapDrew]

We started doing a fouling shot before going hunting for the same reason.

 

[ctdonath]

As posts above aggregate to, there are indeed two factors at work:

1. Don't clean the bore. If you do, fire a few "fouling" shots to gunk it up again. A clean bore doesn't shoot to the same spot as when there's a consistent layer of fouling therein. Cleaning the bore doesn't to much useful, actually.

2. Cold barrels shoot differently than warm ones. Usually it is very consistent, and thus predictable. Figure out where that cold shot goes.

I took Storm Mountain's long range rifle course, and those were two notable points. The head instructor's primary rifle had never been bore-cleaned; the chamber was meticulously polished, but the bore had never been cleaned for (IIRC) over 30,000 rounds of .308. After being told the first day to not clean the bores, the one guy who did anyway promptly got chewed out for it. As for cold bores, we did careful deliberate 100m cold-bore shots twice a day (morning & after lunch) for a week, measuring offset and taking notes. It was suggested that we practice by going to the range and taking only ONE shot: no matter how long it took to get there, no matter how much hassle it was to set up, make only a single shot, pull & record the target, and go home; this makes one focus on the cold bore shot, and emphasizes the reality that when it really matters you'll only get one shot, and that from a cold bore.

 

[taliv]

note that 9 out of 10 gurus disagree about cleaning. the thunder ranch precision rifle class i took had us clean the bores every 10-20 shots.

personally, some guns i clean and others i don't. my practical sorts of rifles, i clean the bores after every 10-20 shots. some guns, like my ar15 that i shoot in HP service rifle, i clean if my next match is an NRA match, and i don't clean if my next match is a CMP match. that's because in an NRA match, you get sighters, and in CMP matches you don't.

 

[U.S.SFC_RET]

Gunsmiths are going to love you guys. You are going to keep them in business if you don't clean that chamber(note I didn't say bore). The chamber loves to develop pits because this is the one area most often neglected in a firearm. I keep my bore clean regardless whatever theory. Yes there is a fouling shot and yes it does have to do with a clean bore. I will not allow a bore to rust.

 

[R.W.Dale]

I will not allow a bore to rust

If you store your rifles properly and don't shoot corrosive ammo it won't be an issue, even without cleaning. I for one have never noticed the almost universally accepted phenomenon that copper fouling and powder residue = RUST

 

[K.L.O.sako]

depending on temp at the range, it could be heat affecting your barrel to stock fit. check for free floating of the barrel. this usually shows up as stringing in the groups. check the action screws also, loose or over tight screws do the same thing.

 

[skinnyguy]

I have a remington 700 .270, and I was noticing the same thing, every shot was raising on the target, though my POA was not. I took the stock off the rifle, and yep, there was a slight designed in bump in the forearm of the stock to support the barrel. I sanded that puppy down to about 50% of the original height. The raising of POI was MUCH less per shot, and it took less time to reach the max lift. I have since sanded the rest of the bump off, but have not yet tested it out yet. Hmmmmmm.... I have a 3-day weekend.....

Good luck and I hope you find your answer soon!!

 

[ctdonath]

the thunder ranch precision rifle class i took had us clean the bores every 10-20 shots.

Ultimately the issue is consistency. If you're going to shoot precision with a clean bore, you have to keep that bore clean. If you're going to be shooting more than 10-20 rounds, the fouling is going to change the POI so you're better off just leaving the thing dirty (each bullet is going to push out any extra goop, keeping it consistent). At Storm Mountain, we went thru over 500 rounds in 6 days, and at nearly 100 rounds per day we weren't going to take a time out for cleaning 10 times each day (in combat you won't have time to clean then either). If, with practice & experimentation, you find that cleaning + a fouling shot or two works for you, fine.

The main thing is: recognize that a clean bore vs. a dirty bore, and a cold bore vs. a warm/hot bore, have different POI. Learn, analyze, cope.

 

[CDignition]

Don't lump thin factory barrels with larger contour Custom barrels. Custom lapped barrels (Rock, Obermyer, etc). Will not change POI with heat and very little with a CBS.

 

[taliv]

At Storm Mountain, we went thru over 500 rounds in 6 days, and at nearly 100 rounds per day we weren't going to take a time out for cleaning 10 times each day (in combat you won't have time to clean then either). If, with practice & experimentation, you find that cleaning + a fouling shot or two works for you, fine.

i think 500 rnds in 6 days is a pretty slow pace, even for "precision" shooting. the thunder ranch course was 500-600 rounds in 5 days (4 if you subtract the classroom time and leaving early on the last day) and we had ample time to clean.

i mean, think about it... 100 rnds / day is like 1 shot every 5 minutes. more realistically, it's like 20 min of instruction, 10 min of shooting, and 30 min of cleaning, scoring and moving around per hour.

 

[rangerruck]

to find out what the problem is, without touching anything as much as possible, HANDLOAD all rounds. If this only happens after a 5 round reload, or a mag reload, you need to fully freefloat the bbl, and bed your action very well. It is having to refind it's 'assgroove' like on a couch, after you do a reload, and shoot 1 or 2 shots.

 

[trstafford]

Got a bargain on a Ruger 30-06 years ago because my friend could not get it zeroed. It was not the barrel but the stock around the action that was moving. A glass bedding kit from Brownell's solved that problem. You could predict exactly how the shots would string from a cold barrel to hot barrel if you did not adjust anything and let the gun cool good between strings the strings would overlap each progressive shot.

 

[Thin Black Line]

If you store your rifles properly and don't shoot corrosive ammo it won't be an issue, even without cleaning. I for one have never noticed the almost universally accepted phenomenon that copper fouling and powder residue = RUST

In the upper midwest where you can have a major temperature swing and fog
can go to drizzle and then snow in an hour, this will = RUST by that night.

 

[ctdonath]

i think 500 rnds in 6 days is a pretty slow pace

To the point of the thread: it's still enough that you won't want to stop, break down the action, clean the bore, and put it all back together every 10 rounds or so, and dealing with the subsequent POI changes as the bore goes from clean to fouled. There's plenty else to be concerned about, and a consistently "dirty" bore gives a consistent POI.

 

[ArmedBear]

Bore cleaners apparently matter.

Many target shooters studiously avoid CLP or anything else with a lubricant in it.

Also, if you protect your bore against rust with an oil, that can affect your first shot.

I use good ol' Hoppes, and I run a boresnake through the barrel every few shots if I'm sighting in. The first shot seems to be right on, for me. Since my .30-06 is a hunting rifle, that's most important to me.

 

[esmith]

just to build on what armedbear said

Yeah when i used to precision target shoot right after cleaning a gun the hoppes we used burned during the first shot. This decreased a lot of my accuracy so we usually just took a shot at the back stop before actually starting to shoot.

 

[ArmedBear]

For hunting purposes, a dry patch or dry boresnake should do well enough if you don't want to blast off a shot when you get out of the car before first light.

That's why you want to avoid using a lubricant as a bore preservative. Lubes, especially teflon, don't wipe out so easily.

 

[skinnyguy]

I got the 700 out today and did some testing after fully removing the barrel support from the stock. That was the problem I spoke of in post #13 in this thread. Between myself and a friend of mine who wanted to test it out, we put 10 rounds of 130gr silver tips through it today, and each shot hit where we aimed, no more barrel rise as it heats up. Both of us are well satisfied that it will do the job come hunting season.

 

[streetstang67]

"skinnyguy", is your stock wood or sythetic?

I've read that sythetics stocks do not warp with temperature change the way wooden stocks do, is this true?