N/A What's this about "cold barrels?"

Jump to latest Follow Reply
Geneeus

Geneeus

Member
Jun 5, 2024
44
66
Spearfish, South Dakota, USA
I posted this question in response to a few people talking about the first shot out of a cold barrel, seeming to imply that the POI would shift as the barrel warmed up. Or am I missing the point? (I often do......)

"
Kinda new to all of this, but I do have a question. Considering that we are shooting compressed air from a storage tank, isn't the barrel always cold? If anything, according to the laws of physics, the air will get hotter when it's compressed into the bottle, and cool down over time until it approaches ambient. When it is released from the bottle, it will be cooler. Or so I believe.

A word of caution: I still believe in the Easter Bunny and the Great Pumpkin......

Geneeus
 
  • Like
Reactions: Arkansas_Airgunner, maxtrouble and markhooper
I've heard the same and I'm definitely not new to all this. I dont know that I've experienced it. Now I have experienced taking a couple shots to settle a regulator, or even to get myself 'warmed up'. But far as warming a barrel? nah. I'm open to having my mind changed, but I personally have never experienced that and place little stock in the notion. I tend to think it's a carry over from firearms where I have experienced it.
 
  • Like
Reactions: Arkansas_Airgunner, markhooper, Ranchibi and 1 other person
Upvote 0
The term came from firearms. In airguns, the term is used more to indicate the first shot after the gun hasn't been fired in a while. This would also hint at the issues of this first shots and how it affects the point of impact (not necessarily temperature related) such as regulator creep and sticky valves.
 
  • Like
Reactions: DesertSilver, Arzrover, maxtrouble and 5 others
Upvote 0
I have been pondering this myself.
The way i see it, yes lead dragging along another surface will create friction and so heat, but at least with the shot cadence i have as a user of a single shot tray i can not see any meaningful / fast rise in barrel temperature.
But of course there will probably be something even if we are pushing things with fairly cold air VS a explosion of gunpowder.
So i think it is pretty small and at least in my case shooting far with a very small caliber ( .177 ) What ever a heating up barrel would give of change i figure would soon get lost in general inaccuracy and environmental effects like wind.

That is of course just my logic speaking, no Danes have a deeper understanding of firearms as such things are generally banned for us mere mortal subjects.
 
  • Like
Reactions: markhooper and Ranchibi
Upvote 0
I talk about cold shots quite a bit. As a hunter it’s the most important thing to me. With an airgun, it’s next level important to me. If the question from the OP is in any way directed at me, I would like someone to find one post by me that has the word bore or barrel in it. If others have been calling it a cold bore or barrel shot in the numerous discussions about it, maybe I’ve overlooked that additional misleading word. But I firmly believe that not many guys believe they have to warm up a barrel temperature wise with an airgun. A cold shot has to do with engine problems, not the runway. Cold is just a single word to describe that my gun has sat for hours, days or weeks.
 
  • Like
  • Love
Reactions: PumaCarl, Arzrover, keith1 and 6 others
Upvote 0
Vetmx said:
I talk about cold shots quite a bit. As a hunter it’s the most important thing to me. With an airgun, it’s next level important to me. If the question from the OP is in any way directed at me, I would like someone to find one post by me that has the word bore or barrel in it. If others have been calling it a cold bore or barrel shot in the numerous discussions about it, maybe I’ve overlooked that additional misleading word. But I firmly believe that not many guys believe they have to warm up a barrel temperature wise with an airgun. A cold shot has to do with engine problems, not the runway. Cold is just a single word to describe that my gun has sat for hours, days or weeks.
Click to expand...
I totally get what you're meaning. I have only had POI issues if a regulated gun sits for awhile, or I drop my gun lol.

I also don't have 100+ yards to shoot which I think would make any "cold" shots more noticeable. If you're shooting 30-50 yards, I wouldn't think it would be easy to spot. If you have POI issues at that distance after a few days of sitting, it'll be extremely pronounced at 100+.
 
  • Like
Reactions: markhooper and Ranchibi
Upvote 0
If my air rifle has sat for a while I will shoot/cycle it a few times before going into the field. It is just to ensure the rifle is functioning and to limber it up since some valves can have a bit of stiction and as well to check zero. I could see referring to that as a cold shot. Not at all like a PB hunting rifle of which many, be they bolt, lever or whatever, after a few shots the barrel can heat up enough to walk the shots. I zero my PB hunting rifles for a cold bore shot. Not applicable to an air rifle.
 
  • Like
Reactions: maxtrouble, markhooper and Dr. Kralenstein
Upvote 0
Agreeing with MushroomPsyche and Vetmx...in the airgun world, the topic of a cold shot is just shorthand for the first shot after the gun has sat idle for a while.

PCPs are subject to factors like regulator creep or O-ring stiction that can contribute to an errant first shot. Springers are subject to factors of their own that seem to be less well understood or accepted as consensus, such as lubricant distribution or seal behavior.

Very little to none of it has to do with the temperature of anything, especially the barrel.
 
  • Like
  • Love
Reactions: PumaCarl, sb327, markhooper and 5 others
Upvote 0
3Crows said:
If my air rifle has sat for a while I will shoot/cycle it a few times before going into the field. It is just to ensure the rifle is functioning and to limber it up since some valves can have a bit of stiction and as well to check zero. I could see referring to that as a cold shot. Not at all like a PB hunting rifle of which many, be they bolt, lever or whatever, after a few shots the barrel can heat up enough to walk the shots. I zero my PB hunting rifles for a cold bore shot. Not applicable to an air rifle.
Click to expand...
You refer to things like I do. I have a dislike for any gun that I have to limber up. And I’ve had a few. With a springer, I’m not sure who has to limber up more before things are on point. Me or the gun. So maybe moving forward so we don’t confuse or offend any powder burner dudes, I’ll refer to a cold shot as a stiff shot. That will really throw a curve at everyone. Maybe start a FX M Stiffy topic.
 
  • Like
Reactions: markhooper
Upvote 0
Vetmx said:
You refer to things like I do. I have a dislike for any gun that I have to limber up. And I’ve had a few. With a springer, I’m not sure who has to limber up more before things are on point. Me or the gun. So maybe moving forward so we don’t confuse or offend any powder burner dudes, I’ll refer to a cold shot as a stiff shot. That will really throw a curve at everyone. Maybe start a FX M Stiffy topic.
Click to expand...
I think that all the options above are right on point.. it either the gun works or probably mostly us that are what is a cold shot.. and I also know that this time of year, I'm not sure if I do get warmed up unless I was stacking firewood, definitely not standing there shooting..
now I have shot spring airguns, PCP guns and powder guns most of my life..I had in my prior collection guns that are extremely rare now and well I wish I still had at least half of them.
now about a cold barrel, in machining there's a tool bit cooler that uses compressed air jetted through a venturi and around a spiral, I forgot what it is called but it basically keeps you tool bit cold and clear of debris.. actually I don't really know if they are still using them much anymore because they have gone to liquid cooling and lubricant..
now I actually have not noticed any difference between a actually cold barrel and one that is warm from shooting.. I would assume that there could likely be a shot placement movement difference between them especially if you have a receiver mount scope.. and possibly even more so if it is dissimilar metals.. just would likely depend on the thickness and design. I was one time working in North Dakota on a farm and I was rebuilding hydraulic cylinders and I went and asked my boss about the spanner wrench,it was a fixed spanner made out of steel and the gland was aluminum..I was told to put both in the heated tack room and do it after I got lunch.. it was quite a way off from fitting but after lunch it fit right in.. note this was a 70° tack room and it was -30° outside plus whatever the wind chill was.. so that to me showed different expansion rates for different metals in extreme temperatures.. oh and there was a couple of days you had to be really careful with tools,I once shattered a ball peen hammer on the first hit when it was extremely cold..
one time I had livestock being attacked by a pack of wild dogs.. and well adrenaline set in after the first shot.. large pack turned on me and I dropped the last one only 10 ft away..I had started at 50+ yards on the leader.. it was a bad day because honestly dogs are my favorite people.. but it had to be done, I had already saved the neighbors kids walking home from school the week before and possibly a month before that they are the legs off my neighbors dog, while it was still alive.. it's horrible what we can cause as humans.. I've never seen wild animals act like those. honestly I think I had one round left in the Henry.. and the barrel was smoking, neighbor actually called me and asked what I was shooting full auto..I told him it was my regular lever action powder burner and the dog pack that ate the legs off his dog was all done..he was very happy but I still felt bad from it all..
that said I have never noticed any change in impact on powder burner.. but all mine were either lever or bolt and open sights..
Mark
 
Upvote 0
Put it this way, it's all obviously going to depend on the barrel metal, but I have recently run into a problem with my new Epoch and running low pressures because of UK sub 12 I have taken the gun from inside with 20c + temps where it fired fine to the range where the temps where 5c and the pellet wouldn't leave the barrel, the barrel is very tight IMO, but the cold contraction of the metal obviously has a marked effect.
 
Upvote 0
I tested the poi for the first through 4th shot from all the air rifles I hunt/pest with late last year. I used one target but a different bullseye for each shot. The guns sat for a minimum of 12 hours between firing the next four shots. It took a few days to complete but was easy to do. The only issue was with my P35-177 using H&N Baracuda FT pellets. I shot my best 30 yd challenge target with this pellet in this gun. But I went back to the Baracuda Match pellets it also shoots well with. That fixed it. Always good to test poi for the first shot with a hunting gun.

My other observation is my first shot velocity is sometimes low if I back off too much on the hammer spring. It can affect poi but not a lot at 30 yards where I normally test.
 
Upvote 0
if you’re testing via target shooting, you need to make sure that your target is beyond your far zero. Also be aware that wind can modulate the vertical POI. The chronograph is the primary means of testing and in reality, the majority of regulated guns will show at least a small drop in velocity. Tune that out as best you can and then see if the result is acceptable for your shooting needs by testing on target at your desired range. If the gun doesn’t pass muster, you either fix it, take up the dry firing lifestyle or start again with another gun. Be aware also that the amount of creep is often proportional to tank/bottle pressure. If you want your creeper to be able to take a pest at 100y after sitting for weeks, store it at a tank pressure that is just above regulated pressure.

Most of the suffering with PCPs is a function of creep and could easily be overcome by having the manufacturer implement a push button plenum purge (in lieu of dry firing).
 
Last edited:
Upvote 0
Geneeus said:
I posted this question in response to a few people talking about the first shot out of a cold barrel, seeming to imply that the POI would shift as the barrel warmed up. Or am I missing the point? (I often do......)

"
Kinda new to all of this, but I do have a question. Considering that we are shooting compressed air from a storage tank, isn't the barrel always cold? If anything, according to the laws of physics, the air will get hotter when it's compressed into the bottle, and cool down over time until it approaches ambient. When it is released from the bottle, it will be cooler. Or so I believe.

A word of caution: I still believe in the Easter Bunny and the Great Pumpkin......

Geneeus
Click to expand...
LOL,That person must think the ammo is going 3000fps
 
Upvote 0
You must log in or register to reply here.
Top Bottom
Back
Home
Forums
Resources
Menu