17remhunter
Active member
Could someone explain to me what is ment by a cold bore shot? Why it it that a fouled barrel shoots better than a clean one? How often do you clean your rifle and why?
Cold bore shot
- Thread starter 17remhunter
- Start date
What I believe is meant, is simply the first shot out of a barrel after cleaning. I always want to know if there is a difference between that first shot and any subsequent shots. On some rifles, there is a difference in POI. Not generally enough to make any difference on a coyote or a deer, but enough to miss a prairie dog or a 'chuck maybe.
In my experience, this is much less of a noticeable phenomena with custom barrels. Can still be observed on a few, but none of the ones I currently own show any difference in POI from that first shot and the next few that I can detect.
Their is also cold barrel vs. hot barrel. Not hot as in hot day vs. cold day. But hot as in longer strings of fire. Many factory barrels shoot noticeably worse and sometimes much worse when hot. A lot of custom barrels do too. But, again, in my experience, it's one of the big differences between an okay barrel and a really good one. A really good one can hold a group together for a 20 shot string. There are rifle issues besides the barrel that can cause one to go to crap when hot, too.
Not all fouled barrels do shoot better than a clean one. Again, this is almost entirely a factory barrel thing. Custom barrels almost always shoot better the cleaner they are. If a barrel actually shoots better when fouled, it will only be up to a certain point. Maybe it shoots better after only a few rounds. But it won't shoot better after 20, unless it's just a really odd/crummy barrel.
My calling rifles, I clean once at the end of the season. These days, they don't have too many rounds each on them in a season. Back when I was killing a heckuva lot more coyotes I'd clean once mid season and once end of season. Maybe 50 rounds or so between cleanings.
My colony varmint rifles, I clean after each use. Each use is often 100-200 rounds.
I've had colony varmint rifles that I only cleaned when I started to miss with them and that might have been 500+ rounds.
- DAA
In my experience, this is much less of a noticeable phenomena with custom barrels. Can still be observed on a few, but none of the ones I currently own show any difference in POI from that first shot and the next few that I can detect.
Their is also cold barrel vs. hot barrel. Not hot as in hot day vs. cold day. But hot as in longer strings of fire. Many factory barrels shoot noticeably worse and sometimes much worse when hot. A lot of custom barrels do too. But, again, in my experience, it's one of the big differences between an okay barrel and a really good one. A really good one can hold a group together for a 20 shot string. There are rifle issues besides the barrel that can cause one to go to crap when hot, too.
Not all fouled barrels do shoot better than a clean one. Again, this is almost entirely a factory barrel thing. Custom barrels almost always shoot better the cleaner they are. If a barrel actually shoots better when fouled, it will only be up to a certain point. Maybe it shoots better after only a few rounds. But it won't shoot better after 20, unless it's just a really odd/crummy barrel.
My calling rifles, I clean once at the end of the season. These days, they don't have too many rounds each on them in a season. Back when I was killing a heckuva lot more coyotes I'd clean once mid season and once end of season. Maybe 50 rounds or so between cleanings.
My colony varmint rifles, I clean after each use. Each use is often 100-200 rounds.
I've had colony varmint rifles that I only cleaned when I started to miss with them and that might have been 500+ rounds.
- DAA
crapshoot
Well-known member
Cold bore shoot is just that. First round fired in a shooting session.
Some barrels after cleaning require a few rounds down the tube to "settle in" and return to it's previous accuracy grouping or actual POI/POA.
Guns need cleaned when accuracy starts to fade or if guns are to be stored for a longer period of time.
YMMV
Some barrels after cleaning require a few rounds down the tube to "settle in" and return to it's previous accuracy grouping or actual POI/POA.
Guns need cleaned when accuracy starts to fade or if guns are to be stored for a longer period of time.
YMMV
Badbrass
Active member
I take a "cold bore shot" as just what it says, when the barrel is cold, the first shot of the group after waiting to cool.
I have a 45/70 that shoots 5" high on the first shot every time it cools. SO when I zero it, I shoot once, let it get cold, and shoot it again, pain in the a$$, but the first shot is the money shot. It takes an hour or so to test a group. The will cloverleaf at 100, the rest shoot very well too, but 5" lower.
I have a 45/70 that shoots 5" high on the first shot every time it cools. SO when I zero it, I shoot once, let it get cold, and shoot it again, pain in the a$$, but the first shot is the money shot. It takes an hour or so to test a group. The will cloverleaf at 100, the rest shoot very well too, but 5" lower.
Hellgate
Active member
Before going on a hunt after a pause of several weeks I will take a dry boresnake that has never had a solvent or oil touch it and run that through the bore (chamber to muzzle) about 3 times to remove any dust or easy to remove verdigris from sitting in the safe. If I clean the bore I use copper solvent followed by a cleaning solvent then at the range I shoot 4 or 5 rounds before going for groups. I believe a super clean bore is going to print differently than a lightly fouled bore.
Bowhntr6pt
Well-known member
A cold bore shot has noting to do with a clean barrel or lack thereof... it has to do with a barrel at ambient temp before heating up, as already mentioned the first shot in a shooting session or sequence.
I won't own a rifle that displays a distinct CBS placement vs. follow up shots.
I spent about fourteen years as a LE Sniper/Marksman and both my issued Rem 700 LTR and Accuracy International fired consistent sub-MOA groups showing no group divergence from the CBS.
This is a pic of a target I made used to track shot divergence from a CBS as well as a zero confirmation/correction.
I won't own a rifle that displays a distinct CBS placement vs. follow up shots.
I spent about fourteen years as a LE Sniper/Marksman and both my issued Rem 700 LTR and Accuracy International fired consistent sub-MOA groups showing no group divergence from the CBS.
This is a pic of a target I made used to track shot divergence from a CBS as well as a zero confirmation/correction.
alf
Well-known member
Cold bore is just that, the 1st shot taken through a cold (not fired recently) barrel.
Now there can be a difference between clean/cold impacts, dirty/cold impacts, and warm/hot impacts.
It's up to you to find out if or how much difference there is in your barrel, & what's acceptable for the task at hand.
I won't get into the how, how much, or when I clean, it can be a deep hole.....
Me either. Haven't had one that did in a long time. Last one that did was a pencil, and I mean pencil barrel Model Seven. All the bedding and floating in the world didn't cure it. Put thousands of rounds through it and killed a ton of varmints anyway. Before making it a donor action. But haven't abided another one since.
- DAA
Bowhntr6pt
Well-known member
wolverines
Well-known member
I don't believe it matters if it's clean or not. Clean bore/cold bore are not the same thing. Sometimes groups tighten as the barrel warms up. Sometimes the group tightens when the barrel fouls up. The goal is to not have this happen.
Every rifle is different. I have a .257 WBY Mag that I have to clean every 3 shots to get tight groups. On the flip side, I have a 300 BO that shot terrible clean and I learned shoots better if I don't clean it at all. One thing that stuck with me a long time ago was something a Marine friend said, "once you're zeroed in, don't clean your rifle until the mission is over". So that's pretty much what I do, just clean it at the end of the season and start the process all over next year.
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coyotecontrol
Member
I agree with what you are saying, but if I may ask: what distance is the above targets at? I also don't see any holes in the target on my screen.A cold bore shot has noting to do with a clean barrel or lack thereof... it has to do with a barrel at ambient temp before heating up, as already mentioned the first shot in a shooting session or sequence.
I won't own a rifle that displays a distinct CBS placement vs. follow up shots.
I spent about fourteen years as a LE Sniper/Marksman and both my issued Rem 700 LTR and Accuracy International fired consistent sub-MOA groups showing no group divergence from the CBS.
This is a pic of a target I made used to track shot divergence from a CBS as well as a zero confirmation/correction.
You also said; "! won't own a rifle that displays a distinct CBS placement vs. follow up shots." But for me, I would have to sell every rifle I got (Sako, Rem., Ruger, etc.) because at 100 yards they are all different CBS. There is one exception tho, my Rem 700 ADL in 270 shoots the Moly coated Barnes "X" Barnes in one hole @100, which is great for that old style bullet.
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coyotecontrol
Member
I had Ruger with a Pencil barrel that I did the required bedding process to, and it too didn't make a difference, but, I did make it shoot really good tho. I put a 5lb pressure point right at the end of the stock, and bingo, that brought the groups down to 1/2 - 5/8” from the original 1 1/4" +.
But I, too, sold the said rifle, for it would really start going wild once the barrel got "hot", which only took a few down the tube to do that.
alf
Well-known member
That's just a picture of the target that he uses.
"This is a pic of a target I made used to track shot divergence from a CBS as well as a zero confirmation/correction."
coyotecontrol
Member
Bowhntr6pt
Well-known member
@coyotecontrol
Yes, just a copy.
None of my "precision" oriented rifles display a significant deviation from a CB shot to subsequent shots. Below are some pics to show what I've documented with multiple rifles. I'm not taking your post as a call out but just for those who might think I'm stretching the truth.
When I say deviate, I'm talking 1/2 to 3/4 of an inch from the main radius of the group. All shot at 100 yards.
AR15 with a DPMS barrel... all five shots starting from CB...
Aero M5 with 110gr (,308 Win)...
Ten shots including CB from a 24" bull-barreled AR15...
Savage .223 Bolt gun...
DPMS AR10 with 18" SASS barrel...
While I'm no longer an operational Sniper, I still carry my issued Rem 700 LTR and I just took these pics from my data book to show the documentation we keep concerning CB shots and subsequent shots...
I certainly do agree some rifles will have a distinct CB shot that differs from a subsequent group... but I have perhaps 25-30 precision oriented rifles and NONE of them have that issue... if they did, I'd re-barrel or send them down the road.
I have data books on all my rifles and can post pages of similar targets but I think this should suffice.
Bowhntr6pt
Well-known member
Another thing... I don't clean my rifles after a range session. I will run a VERY LIGHTLY applied CLP patch down the bore and that's it. I clean when groups open up which seems to be between 450-550ish rounds.
Plant.One
Well-known member
buddy of mine has one of those SASS barrels on his g2 dpms, and like yours with fgmm, damn thing is a shooter! holds about ½ moa out to 500, and i've seen him go 2 for 3 on our club 1½" challenge gong at the same distance. and the 3rd didnt miss by much!DPMS AR10 with 18" SASS barrel...
he had originally bought it as a 16" carbine, but that barrel was *trash*. 4-5 MOA depending on ammo, including fgmm and hornady match 168 amax. he got it sent back under warranty just as big green was folding up shop and all they could offer him was a SASS barrel.. i was like "YES! SNAG THAT! QUICK!". turned a turd into a tack driver for him!