Cold/Clean Barrel vs . . . not :)

**Twoboxer** · April 30th, 2013, 01:18 PM

Lots of answers to load development questions seem to include the advice "let the barrel cool" and/or "clean the barrel" between shots/groups.

For range use, there doesn't seem to be much point in developing a load that only shoots well from a cold/clean barrel. My inclination would be to shoot the load-development groups with a cold, warm, or hot barrel depending on my intended use, and cleaned at intervals reasonable for that firearm.

So for an AR15 I love to shoot, its a warm/hot barrel. For a medium/large game hunting rifle, a cold lightly-dirtied barrel.

Please help me out here if I'm missing something.

**spaideas** · April 30th, 2013, 01:33 PM

I think you are right on the money with your assertation. A round that you plan on using for as a hunting round would benefit from being fired from a cold bore for developmental purposes. That's how it will fired in the field and will mimic the results while developing the load. I would probably just run a boresnake down the bore in leiu of a full cleaning. Develop loads for the AR with the barrel hot and dirty.

Rick

**Tomcat088** · April 30th, 2013, 01:39 PM

Originally Posted by Twoboxer

Lots of answers to load development questions seem to include the advice "let the barrel cool" and/or "clean the barrel" between shots/groups.

For range use, there doesn't seem to be much point in developing a load that only shoots well from a cold/clean barrel. My inclination would be to shoot the load-development groups with a cold, warm, or hot barrel depending on my intended use, and cleaned at intervals reasonable for that firearm.

So for an AR15 I love to shoot, its a warm/hot barrel. For a medium/large game hunting rifle, a cold lightly-dirtied barrel.

Please help me out here if I'm missing something.

I think this is a very good question, and one that I haven't really heard asked in this particular instance. Honestly, I don't think that you're missing a thing. I personally have never given the advice of a "clean" barrel when it pertains to developing loads. I'm not opposed to developing groups with a cold fouled barrel, if that's how it will be used. I would say that cold vs. warm (ie not hot), I don't worry about a lot unless I already know that I have a barrel that likes to string when it gets warm. As a generality though, I do agree with you that you should develop a load for the way that it will be used. If you normally will be shooting it through a firearm with a warm barrel, well then for best accuracy in that sort of use, you want to develop the load in those conditions.

I know quite a lot of BR guys, and the ones that I know don't even develop their loads with a clean cold barrel, they're always fouled the way they would be for a competition. Those guys put their rifles away clean, but they're always fouled at the competition before they're shot for score. Since I'm a long range guy that does what would be considered "tactical" shooting, and I'm more interested in cold bore hits, my rifle is ALWAYS fouled. The reason being that when it's a clean cold bore, there's deviation in the point of impact until it gets fouled. I'd say keep doing what works for you, I use a process similar to what you're describing, and it works well for me. I'm curious about some others chiming in, and how they do things. I always figured that was the norm, but it may be that it's not, lol.

**Twoboxer** · April 30th, 2013, 04:26 PM

Originally Posted by Tomcat088

. . . I would say that cold vs. warm (ie not hot), I don't worry about a lot unless I already know that I have a barrel that likes to string when it gets warm . . .

Yup. I've "discovered" that my RR LAR15 shoots pretty much the same from warm to better-cool-it-off-now lol. OTOH, my Sako 85 .223 begins to string shots unless I rest it periodically. And then a little later it will throw shots 'cuz its dirty while the LAR will just keep on shooting.

Originally Posted by Tomcat088

. . . The reason being that when it's a clean cold bore, there's deviation in the point of impact until it gets fouled.

Finally, with the Sako at 100 yds from cold I'll get (eg) a 1-out/4-tight group 1.25" overall, but the next 5-shot group will be all 5 inside 0.75".

**dk99358** · April 30th, 2013, 05:56 PM

I guess I sort of do this by default, I don't own anything that gets fired rapid and repeated. So my load developlment is fire 3 shot groups and then wait for it to cool before I fire the next 3 shot group.

Over the years, I have noticed a difference in dirty/versus clean impact in most of my rifles so I do not clean them after sighting in, they wait until hunting season is over.

**Edg** · April 30th, 2013, 06:00 PM

I don't.....I fire 1 or 2 proven bullets to warm the gun up then I load 5-10 of my test loads and fire them at a rate of about 1 each breath....The break in between is how long it takes me to reload the magazine. Ill run a bore snake through the barrel about every 50 rounds. Ive not noticed a difference between cold and hot or clean and dirty.
I shot one of my known accurate match bullets to warm up my gun the other morning and it hit the bullseye.

**nachogrande** · April 30th, 2013, 06:23 PM

a lot will depend on the gun also. some if lucky don't fluctuate much between cold/warm/hot or fouled/clean, other guns may fluctuate greatly.

**Twoboxer** · May 1st, 2013, 12:06 AM

Originally Posted by nachogrande

a lot will depend on the gun also. some if lucky don't fluctuate much between cold/warm/hot or fouled/clean, other guns may fluctuate greatly.

Right. That was an inherent assumption in my own approach, but it should be put right up front.

Ultimately the gun will set the limits for how you will shoot it - clean or fouled, cold or warm or hot. And so that's how you should conduct your load development, not with an artificially clean and/or cold barrel.

**stainless** · May 1st, 2013, 12:44 AM

Originally Posted by Twoboxer

Right. That was an inherent assumption in my own approach, but it should be put right up front.

Ultimately the gun will set the limits for how you will shoot it - clean or fouled, cold or warm or hot. And so that's how you should conduct your load development, not with an artificially clean and/or cold barrel.

Others have stated that what you are questioning as being correct thus I have nothing to add to it. Just wanted to state your analytical outlook and critical thinking abilities are working. In other words, you frigging got it. Enjoy shooting.