Barrel break in accuracy

If you haven't jumped the Hammers a bit, give them a running start, say start at .050" off the lands. Or seat them to the first band.

I am actually going through this with a rifle myself. It just has not given me good groups with a few bullets, powder, primer combos yet. Enough that adding up prices on expended components, are about half a barrels worth. And these days that's alot of components $$$.
Ok, I'll try .050 jump. That would put my OAL at 3.000". There's a lot of that bullet in the case, but it is what it is. It might be just fine. I was at .030 with 4 rounds yesterday, but I think that might have been a bit much. I'm gonna start at 49 grains of Rel 26, and see what I have.
 
Last edited:
So, I just got my rifle back from the gunsmith where I had a new Hart barrel put on, and some work done to the receiver. Caliber is 25-06. I'm just a little disappointed in the fact that with 116 grain hammers, I can only get to 3.050 OAL before I'm into the lands, but not sure I'm concerned with that yet. First 20 rounds thru the barrel have yielded pretty mediocre results as far as accuracy, so I guess my question is this. Would it be normal for a rifle to shoot more accurately after say, a hundred rounds are put through it, or not so much. I haven't done any load work-up yet. I figure I need to get some rounds thru it before I go there, but just curious as to what you really good shooters' opinions are as to accuracy and a new barrel.
Just follow their recommended break in procedure faithfully.

Personally I don't expect peak accuracy until I have somewhere between 50-100 rounds through the barrel.

Breaking in a new barrel is kind of like breaking in a new cast iron skillet, when it's properly seasoned you'll know it.

At some point you should see both an increase in velocity and a tightening up of groups, when you hit that point it's probably there and you can start working up accuracy loads and tweaking seating depth.
 
It is easy to get excited. First, I would decide….do you want it throated for hammers seated long, or are you ok seated at this length. I would settle that in my mind.

Then I shoot a ladder looking for a light load that fully forms the case. This load is odd in that bullets are seated slightly into lands and with a false shoulder that closes slightly firmly. This is typically a light load that forms the case….oddly, it usually shoots quite well with whatever bullets.

Then, with formed, annealed, fl sized brass, I load a ladder to find pressure and see where the bullets are flying. If they fly to similar POI with variation in powder charge. If they are not flying to similar POI, I'm thinking about a next bullet.

If ok, I will shoot some 3 round groups varying charge weight to get to a rough weight for use when setting oal. I shoot 2 shot groups looking for seating depth…3 if it looks promising. The 5 groups of 5 to find best Sd and best accuracy charge weight. If below target, I might fine tune depth.
 
It is easy to get excited. First, I would decide….do you want it throated for hammers seated long, or are you ok seated at this length. I would settle that in my mind.

Then I shoot a ladder looking for a light load that fully forms the case. This load is odd in that bullets are seated slightly into lands and with a false shoulder that closes slightly firmly. This is typically a light load that forms the case….oddly, it usually shoots quite well with whatever bullets.

Then, with formed, annealed, fl sized brass, I load a ladder to find pressure and see where the bullets are flying. If they fly to similar POI with variation in powder charge. If they are not flying to similar POI, I'm thinking about a next bullet.

If ok, I will shoot some 3 round groups varying charge weight to get to a rough weight for use when setting oal. I shoot 2 shot groups looking for seating depth…3 if it looks promising. The 5 groups of 5 to find best Sd and best accuracy charge weight. If below target, I might fine tune depth.
Lots of good information here. Thank you
 
Make sure the bedding is good/ all screws ect and then move to a different powder if that doesn't work try a different bullet. I've got a rifle that shoots in the .2-.3's regularly and with a load it doesn't like with a different powder/ bullet I've seen .8-1.3" groups. My point is that if your barrel doesn't like something it may never shoot it well so don't get stuck on one combo. My limit is 3 bullets/ powders. If a rifle won't settle down with 3 then I'm moving on. But that's usually 300 rounds or so so I'm definitely giving them a shot. Pun intended.

Sometimes it's best to try a ladder test even at 100 yards and just work up to pressure. Do that with a couple combo's and one may really stick out as having more potential. If one ladder shows 4 moa and one shows 1.5 moa group then that'll give you some good clean data to make a easy decision. It's a good way to test multiple bullets/combos and find a load with less hassle and do it using less components.
 
So, I just got my rifle back from the gunsmith where I had a new Hart barrel put on, and some work done to the receiver. Caliber is 25-06. I'm just a little disappointed in the fact that with 116 grain hammers, I can only get to 3.050 OAL before I'm into the lands, but not sure I'm concerned with that yet. First 20 rounds thru the barrel have yielded pretty mediocre results as far as accuracy, so I guess my question is this. Would it be normal for a rifle to shoot more accurately after say, a hundred rounds are put through it, or not so much. I haven't done any load work-up yet. I figure I need to get some rounds thru it before I go there, but just curious as to what you really good shooters' opinions are as to accuracy and a new barrel.
If you're attempting to load for accuracy-then stop measuring C.O.A.L. You should be measuring B.T.O.
 
It will slowly tighten up, but shouldn't be that far off. Either add some more jump or switch bullets. Did you go with enough twist for the hammers? And did you Smith throat you chamber for that bullet?
 
I had a rifle built with a hart barrel about a year ago chambered in 6.5 Weatherby RPM. After initial break in it would shoot 1/2 moa groups with factory and even some heavy 156 Berger's. I was super excited. At about 100 rounds it opened up to 2-4 moa and no amount of cleaning would change it. Looked in it with a borescope and found porosity issues near the muzzle. We are going to cut it back and recrown it and pray that works. Otherwise, replace it it wit not a hart barrel.

Good luck
 
I don't expect great grouping until I have "fire formed" my cases to the new chamber. I have seen two inch groups with new cases and new chamber shrink to less than one inch after "fire forming" the new cases to the new chamber.
I have a Ruger 77 in 25-06 that shoots very well, under .375 for five shots, with a charge of 4831. This is a factory barrel on a gun I bought used. I have had the best groups with the Sierra 117-120 grain bullets. I only use this rifle on deer and antelope so I haven't tried any of the premium bullets. Frankly, I am so pleased with the Sierra bullets I am not looking forward to trying any other bullets.
Just my two cents and YMMV.
 
Top