Seating Depth Again

[Old Navy]

Just received a batch of 107 SMK for my 6BR from Bruno's. Tried my favorite loads with Varget, H4895 and Reloader 15. Settled on #15. Found a load that shot consistently in the high .2 to .3s. I started at what I think is -.015 off using my Hornady Lock-N-Load tool. I have done this test many times over the years but never saw the groups open and close like this. Thought some might be interested in this.

 

[JEFFPPC]

I shoot the same bullet in a pair of 6brxs. I have a suggestion for you to try. I look for repeatable 3 shot groups in the ones and zeros. Start with a square mark on the bullet from the lands. Start backing t.he bullet into the case .005 at a time. I do this with 2 shot groups to start. When you get to where 2 shots are going deep into the same hole, shoot a third. When you think you have found the sweet spot experiment .001 a time or two on each side . When you can shoot back to back groups in the ones and zeros your good to go.As with all load developement be sure to do this over flags. Get it the best you can than go a tenth either side with powder to refine. At this point if I feel there is room for improvement I sill play a bit with tuner usually to make 5 shot groups rounder. I have only ever jumped this bullet in one barrel. Two current barrels are .016 into lands and .019.

 

[JB10]

Try a light next tension and seat .010 into lands. This has worked best for me with berger 105 hybrids and a few others i know.

 

[JB10]

this was a 5 shot group loaded at .010 jam with verry light next tension

 

[Old Navy]

Just received a batch of 107 SMK for my 6BR from Bruno's. Tried my favorite loads with Varget, H4895 and Reloader 15. Settled on #15. Found a load that shot consistently in the high .2 to .3s. I started at what I think is -.015 off using my Hornady Lock-N-Load tool. I have done this test many times over the years but never saw the groups open and close like this. Thought some might be interested in this. View attachment 1190175

The above was not a demonstration of my shooting ability. I was shooting in a gusty 6 to 18 mph wind coming at me from 10 o'clock. It was literally shaking me and the bench. I found out all I needed to know.

 

[Stan Taylor]

View attachment 1190209 View attachment 1190209 this was a 5 shot group loaded at .010 jam with verry light next tension

Interesting to say the least in terms of light tension what would that tension measure on a century 21 guage or a K&M type seater.

 

[JEFFPPC]

The above was not a demonstration of my shooting ability. I was shooting in a gusty 6 to 18 mph wind coming at me from 10 o'clock. It was literally shaking me and the bench. I found out all I needed to know.

So.....you really think shooting in those conditions with the bench shaking gave you any valid information. To me that is wasted rounds down the barrel. Testing is great but I question what you just did .

 

[Old Navy]

So.....you really think shooting in those conditions with the bench shaking gave you any valid information. To me that is wasted rounds down the barrel. Testing is great but I question what you just did .

Went out again last night it perfect conditions and got the same results although all four groups were smaller. I am retired and have one hobie, shooting. If the wind had been at 90 degrees or at 1K i would not have got out of the truck. No rounds are wasted when I am having fun.

 

[JEFFPPC]

Ok Old Navy, I agree with you on that one.

 

[JB10]

Interesting to say the least in terms of light tension what would that tension measure on a century 21 guage or a K&M type seater.

Loaded round measures .269 and i use a .269 neck bushing. This allows enough to keep bullet in brass and when you load the round it will be against the lands. The bolt will seat deeper and you get constant seating depth with throat wear.

 

[Stan Taylor]

Loaded round measures .269 and i use a .269 neck bushing. This allows enough to keep bullet in brass and when you load the round it will be against the lands. The bolt will seat deeper and you get constant seating depth with throat wear.

Thanks for your response but that didn't help me arrive at a number I tried what you said my bullets won't stay in the case with any tension at all an my loaded round is .269 od.

 

[JB10]

Thanks for your response but that didn't help me arrive at a number I tried what you said my bullets won't stay in the case with any tension at all an my loaded round is .269 od.

Try a .268 bushing. Maybe i have less spring back in my brass than you. Im useing lapua brass. I can seat the bullets with basically my fingers but have to work at it a bit. I use the press to do it straight.

 

[JEFFPPC]

Thanks for your response but that didn't help me arrive at a number I tried what you said my bullets won't stay in the case with any tension at all an my loaded round is .269 od.

Were the necks annealed, or is it work hardened? Just an idea, I would think if it's work hardened this method might not work.I will try it out next week with anealed brass. I am curious.

 

[Stan Taylor]

Were the necks annealed, or is it work hardened? Just an idea, I would think if it's work hardened this method might not work.I will try it out next week with anealed brass. I am curious.

It would definitely be interesting if you can use the same size bushings as the loaded round.

 

[JB10]

I have not done it with any other caliber, just my 6br. A friend of mine did it to his 6br and now his 6 dasher. Its my only rifle i have set up only for a bench rifle. The rest of mine i use a .001 smaller bushing than loaded round measures so i have a little more tension for when i use them for varmint and dont want to accidentally stick a bullet in the throat if i have to pull the round out of the chamber.

 

[JFrank]

I have a 6 Br I can’t seem to get away with that light of bullet hold it just shoots kinda wild until I get a couple thousand or even three seems stable and repeatable.
Interesting

 

[stacy]

IM WITH JB10 I CAN GET BUY WITH .001 SMALLER BUSHING THAN A LOADED ROUND AND IT DOES WELL IN MY XP100 6BR RIFLE