Velocity Jump on new barrels

Doug Herold

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This year I had a Proof barrel put on a custom gun I had built. After @ 100 rounds through the gun, I got a 150fps increase in mv. Is this common only with the Proof???... or do other barrels jump their velocity after break-in?
 
Normally any barrel will increase in velocity after break in. they will also slow down in badly fouled barrels. accuracy will start out poor and improve during break in . Then settle in when break in is complete, at this point you can start load development.

Some barrels by nature are a little faster than others because of bore diameter differences.

Just my opinion based on many years of testing new barrels.

J E CUSTOM
 
^^^What he said.

Your velocity will increase as your barrel reaches copper eqilibrium... and then slowly decrease as your copper fouling increases, and then it will drop off steeply along with accuracy when you reach a certain point.

Magnums usually have a shorter period of equilibrium, while moderate rounds like the 308 can go a long time before they need copper removal. My one savage 10 is good for about 500 rounds between copper removal. It obviously varries by barrel, but its goes generally along those lines.
 
Normally any barrel will increase in velocity after break in. they will also slow down in badly fouled barrels. accuracy will start out poor and improve during break in . Then settle in when break in is complete, at this point you can start load development.

Some barrels by nature are a little faster than others because of bore diameter differences.

Just my opinion based on many years of testing new barrels.

J E CUSTOM

Thanx, J E, I was hoping to get your opinion on this. I have a follow up question for you and everyone else:
I few years ago I cleaned my rifles meticulously after shooting. One day I had dinner with a SEAL who is a Team Leader for a group you would recognize. At that time he had spent 17 deployments in the sand. I asked him, "what do you do to your gun after deployment when you get home?" He told me he takes everything apart in his rifles and gives them a thorough cleaning — except the barrel. A long as it's shooting accurately, he leaves it alone. I stopped cleaning my gun. Only when I begin to loose accuracy or velocity do I touch the inside of my bore.
This brings me to my question. I have used all kind of products on the market to address copper fouling. Currently, I am using the KG 12 for copper and KG 1 for carbon. I am not showing telltale blue on the patch, however. I first do the KG1, then follow with the 12. I wonder if I am getting out the copper?!! I don't have a "scope" and can't see down the bore due to the "breaks".
I used to use the J-B Bore Cleaning Compound and Bore Bright, but I read that it could damage the barrel. I have a Wilson barrel (Cooper), a Proof barrel (Gap ), and a Rem 7mag Sendero. I certainly don't want to damage the new Wilson barrel or the Proof.
What is your opinion on using these or other products???
(Also I use and really like Butch's Bore Shine)
Thanks for the feedback
 
I've never seen one increase by 150fps, but I've seen 50-75.
I don't clean as much as some guys and more than other's, there are a lot of varying opinions on this, but most of my rifles get cleaned between 50 and 80 rounds, and I never remove all of the copper. A bore scope is pretty helpful to know what your actually getting done, it's a bit of guess work without one, but you can get by just fine without one.
I don't own a bore scope, but my smith lives about 10 minutes away, so it's easy to bring a rifle down every once on while and make sure I'm getting them clean enough.
 
Doug Herold, I don't think the KG product will show blue when it is removing the copper. After you think you have it clean, try using some Butch's or Bore Tech Eliminator. The blue will show up if you missed any copper OR if any of your jags or brushes have copper or brass in them. Make sure your jags and brushes are copper and brass free or you will get blue color all day long.
 
This year I had a Proof barrel put on a custom gun I had built. After @ 100 rounds through the gun, I got a 150fps increase in mv. Is this common only with the Proof???... or do other barrels jump their velocity after break-in?

150 fps is a large jump, potentially unsafe. I'd watch your pressure closely. If you were at or near max before the velocity increase, you're most likely over pressure now. The jump is usually around 75 fps.
 
Thanx, J E, I was hoping to get your opinion on this. I have a follow up question for you and everyone else:
I few years ago I cleaned my rifles meticulously after shooting. One day I had dinner with a SEAL who is a Team Leader for a group you would recognize. At that time he had spent 17 deployments in the sand. I asked him, "what do you do to your gun after deployment when you get home?" He told me he takes everything apart in his rifles and gives them a thorough cleaning — except the barrel. A long as it's shooting accurately, he leaves it alone. I stopped cleaning my gun. Only when I begin to loose accuracy or velocity do I touch the inside of my bore.
This brings me to my question. I have used all kind of products on the market to address copper fouling. Currently, I am using the KG 12 for copper and KG 1 for carbon. I am not showing telltale blue on the patch, however. I first do the KG1, then follow with the 12. I wonder if I am getting out the copper?!! I don't have a "scope" and can't see down the bore due to the "breaks".
I used to use the J-B Bore Cleaning Compound and Bore Bright, but I read that it could damage the barrel. I have a Wilson barrel (Cooper), a Proof barrel (Gap ), and a Rem 7mag Sendero. I certainly don't want to damage the new Wilson barrel or the Proof.
What is your opinion on using these or other products???
(Also I use and really like Butch's Bore Shine)
Thanks for the feedback


All barrels respond differently to a cleaning regiment so I try to find out what the barrel likes first.

My experience has been that a clean barrel is the most accurate. At some point a barrel fowls to the point that it becomes very consistent and this is what most match shooters look for because they cant clean after each relay. If you leave the barrel fouled, load development should be done in this condition not in a clean condition.

I have followed the progress of custom barrels from the first shot on
and found that as the barrel broke in it got faster.until break in was complete. Then it settled in to a consistent velocity and as it became fouled velocity dropped very little but accuracy became worse as the barrel fouled. This normally occurred at 4 to 7 rounds from clean depending on the barrel itself. (I think this is the reason that it is hard to shoot a great 5 shot group) because it always seems like a flier happens on the last round. (It could also be shooter stress because he tries so hard to place that last bullet in the center of the group and not mess up a beautiful group.

Once you get through the point that fouling effects the consistency,
you may fire several hundred rounds before the bore has to be cleaned due to accuracy issues.

My match rifles had to be used fouled, because they would be required to fire 100+ rounds during the match with no time to clean.

My hunting rifles only require 1 shot (Hopefully) and cleaned after several hunts (3 or 4 shots). I work up my hunting loads by cleaning after each test load so they are all tested in the same conditions to evaluate each load fairly.

So to sum this up, I have different cleaning regiments for hunting and match shooting based on accuracy requirements needed under the conditions.

As to checking if your barrel is clean or not, Some solvents done turn the patches green and some do, so to find out, try some of your Butch's in the bore and if it doesn't turn green, your cleaning is going OK.

Fouling is an interesting beast. During brake in it prevents uniform break in (The reason you clean after each shot) once a barrel is broken in It tends to protect the bore from wear even though it may hurt accuracy at some point (This is one of the reasons that factory barrels come fouled from test firing).

I clean all of my firearms frequently because fouling can damage the bore after while because powder residue can attract moister and cause corrosion, Clean and oiled cant. everyone has there opinion on cleaning frequency and the amount of time and quality of the cleaning, but having worked on many firearms that were not taken care of or cleaned often or not at all and compared to the ones that were meticulously maintained, there was a total difference in there condition.

I don't recommend any bore solvent that has abrasives because they shorten barrel life and should not be necessary. In my opinion, It is counter productive to worry about barrel life and then use an abrasive cleaner of bullets in the bore. There are to many good solvents available that only address the fouling.

Sorry for the long explanation.

J E CUSTOM
 
I agree with most of what has been typed in the thread. One thing I did not see mentioned is the fact that sometimes once fired brass will cause more pressure therefore more velocity than new brass. You mentioned 100 rounds. Did that happen to be how many pieces of new brass you had?
 
I've been blessed to be able to afford a couple of GA Precision rifles. When I asked George Gardner about barre break in, he said just shoot it and clean it at the end of the day the first 2-3 times. Then expect to see velocity increase by 75-150 fps after somewhere between 100-200 shots. Velocity will stay at that new speed until the throat starts to go, then you should check the distance to lands and readjust. After those changes, once the barrel starts to lose velocity again, it's time to rebarrel.
FWIW Both of mine were built with Bartlein barrels.
 
RBros was dead on with my 6.5x47. Said it would speed up after about 200 rounds. It did. Velocity increased almost 100 fps. Barrel is a 26" Broughton.
 
Yep as said before I always do about 50 rounds of box ammo to break it in and get zeroed. Then I do load work. After another 100 rounds I'll check velocity again and adjust as needed.
To make cleaning easy try boretech. They make it very simple and easy to clean.
 
I think everyone hit it on the head with copper equilibrium. What I will add is it helps to keep a barrel log, with shot count and MV averages. You don't need to do MV every range session. I document speeds every 250 round after barrel break in.
 
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