Expected group size breaking in new barrel?

[CA_Shooter]

I have a RPR, and recently installed a 6.5 creedmoor Krieger barrel because I shot out the stock barrel. I’ve only broken in the stock barrel before, and according to Krieger’s FAQ they advise to clean it after each shot until the barrel seems to not be fouling.

I took the barrel’s first 40 shots today with some stock SST Hornady rounds.

I cleaned it about 10 times. Shot no more than 5 rounds without cleaning.

My groups were all over the place. Not sure if it was me being rusty, since I’ve barely shot in the last year with a newborn and Covid. Got some group sizes as bad as 2 inches at 100 yards.

So noob (for new barrels) - is this to be expected with that amount of cleaning AND a new barrel? Or am I just really that rusty? Or...who knows?

 

[Evan]

stock SST, as in the factory affordable line of ammo for deer? I wouldn't worry too much as that's not likely to give you the best performance. You could try a box of Hornady Match or Federal Gold Medal and see if it groups better.

 

[DngBat7]

Not the correct ammo. Evan is correct to try some Hornady eld 140grain match. I have same setup and no problems getting 1/2 to 1/4 moa. That Kreiger is most likely super accurate.

 

[CA_Shooter]

I generally load 140 ELDs, but considering I was breaking in the barrel I used the stock SSTs (bought for the brass years ago when on super sale).

With the old barrel I still grouped it less than 1 inch at 100 with the SSTs

Do you think all the cleaning would have opened it up...that much?

 

[Evan]

I think if you reload then that Krieger will show you a whole new gear. My stock RPR shoots very well with 147ELD and Imr4350, RL17, or H4831sc. Consistently 0.5MOA and smaller way out there. I'd be shocked if that Krieger doesn't do better.

 

[Zero333]

Some of the Hornady factory ammo can be pretty crappy accuracy wise so don't rely on it for any input.

During break in I found accuracy to be no different than after break in.

Most important for me is to clean the barrel really well before thinking of shooting through it. If it's a hand lapped premium barrel, I just clean it before shooting and skip the break in.

 

[AllenOne1]

Probably a combination of lower not bad quality ammo and you being rusty. Remember you are learning a new rifle with different balance than you had before. Shoot some more give it a little time and it will come around.

 

[Hohn]

Some of the Hornady factory ammo can be pretty crappy accuracy wise so don't rely on it for any input.

147 factory match ammo was a train wreck in my Savage. It didn't seem capable of going under 1.5". That's not "match" in my book. Yet hand loading the 147 with RL16 got me 3/4" pretty regularly when close to the preferred OAL. Which isn't super impressive, but about as good as I can expect an OEM savage barrel to shoot in a $300 rifle off a bipod and squeeze bag.

I never shot any factory 140 ELD ammo, but burned several boxes of them in handloads. My first test of mild loads with RL15 was a 5 shot bughole of about 1/2". Pretty slow with only 36.5 of RL15, but it landed right on a sweet spot. My experience is that the 147s can't quite run with the 140s for pure accuracy. But the extra BC at 600+ might matter more to you.

Hornady factory ammo has good quality brass in terms of consistency, it's just a bit soft if you push it-- the pockets will go somewhat fast.

If I were going to assess a 6.5cm based on factory ammo, I'd probably go the 140 ELD route.


I also haven't seen accuracy improve after break in. And premium hand-lapped barrel requires no break in that I can tell. Foul it and get busy.

 

[Dave Zander]

I have a remington 700 action re barreled in 6.5 creed moor , Kreiger 26".
I shot 10 different charge weights of H4350when it was brand new, Lapua brass New, cci450's, 140 grain Berger Hybrids 10 shots were easily all inside a 1" circle.

 

[CA_Shooter]

Well coming back to this post, finally got to shoot the barrel with my own rounds and was pleased. Still need to further tune the loads but here are the groups.

The constant cleaning and the SSTs were the culprit

 

[B muzguy]

Well coming back to this post, finally got to shoot the barrel with my own rounds and was pleased. Still need to further tune the loads but here are the groups.

The constant cleaning and the SSTs were the culprit

Most 6.5 Creedmoor with 140 grain Berger hybrid and H4350 CCI BR primers Hornady brass it will start to show extreme accuracy around 41.5. 42.0. 42.5 some have even gone to 43.0 grains .. but use caution my load is 42.5 bughole. 0.010" jump

I shoot three clean shoot three clean shoot five clean Shoot five then start load development you will get no copper after the first three in my experience. And if you do get copper it is extremely light so light that C4 carbon remover removes it.