Concentricity Question

[Deputy819]

So, I've been reading/researching on something (haven't been able to shoot or test again yet) and I stumbled on something that may very well be an "A Ha" moment. Probably gonna take a few "gut punches" from some of you on this one. It's all good. From the Get Go with this rifle I've been dipping my case necks into mica powder prior to bullet seating as recommended by my Smith. I'm reading that maybe I shouldnt be doing this as it could cause inconsistencies/variations in friction as the bullet leaves the case upon firing. Could this possibly be my problem?

 

[dmoon]

I always use a .177 caliber brush to put imperial dry lube inside my necks prior to seating bullets, it's the best thing I've ever found to get my SD's down where I want them.

 

[ShtrRdy]

I don't think that would explain the difference in group sizes. Lubing the inside of the neck before seating bullets should improve the velocity consistency, although I haven't proved this to myself yet.

 

[Deputy819]

@ShtrRdy & Dmoon
That's what I thought too until I read a bunch of stuff online this morning (not LRHM) and shooters were saying NEVER to use anything inside a case neck prior to seating a bullet. One went so far to say that they had tried mica/graphite in their necks for lube and their rifle sprayed bullets "All over the show" as a result (quoted). Maybe something else could have caused that and they just blamed the dry lube. Who knows. In any case, there were a lot of folks crying "Foul" for using any lube at all and was wondering what you guys thought about it.

 

[Dr. Vette]

I know of one shooter on this site who regularly shoots to 2000+ yards, keeps his rifles to 1/2 MOA or less, and always uses the Imperial graphite lube before seating bullets.

If it's good enough for him, it's good enough for me.

In addition, if you did it to some of your loads, but not all, and could see a pattern then I might agree. Given that you don't seem to have a pattern, I don't think it's the graphite.

Did you read the current thread on annealing?

 

[Deputy819]

I know of one shooter on this site who regularly shoots to 2000+ yards, keeps his rifles to 1/2 MOA or less, and always uses the Imperial graphite lube before seating bullets.

If it's good enough for him, it's good enough for me.

In addition, if you did it to some of your loads, but not all, and could see a pattern then I might agree. Given that you don't seem to have a pattern, I don't think it's the graphite.

Did you read the current thread on annealing?

The only consistent "pattern" I have is one of INCONSISTENCY. One tight group followed by 20 horrible ones. Have been following that annealing test thread like a hawk.

 

[TwoMore]

Its my understanding that the powder has graphite in it to aid in manufacturing and will dry lube the bore, I always run a dry patch and then another with graphite down my bore after I clean. usually my first shot will be up in the group and copper fouling is drastically minimized. I use a ultra sonic cleaner and I will use a q-tip with dry lube on the insides of my case necks after I prep them

 

[Rich Coyle]

The only consistent "pattern" I have is one of INCONSISTENCY. One tight group followed by 20 horrible ones. Have been following that annealing test thread like a hawk.

I had a solid 1 1/4" rifle. Every once in awhile it would do a 1/4" or 5/16" group. I think that's what you have.

 

[Deputy819]

I had a solid 1 1/4" rifle. Every once in awhile it would do a 1/4" or 5/16" group. I think that's what you have.

Key word being HAD.....as in GOT RID OF...right?

 

[Deputy819]

Check out the top left diamond. Solid 3/8" group at 200 yards at 44.6 grains of powder and a COAL of 3.446 (ogive to cartridge base). Was testing seating depth only on this quick test last weekend. Left center diamond was same powder charge only moved .001 further into the case and NO group whatsoever. Should .001 make that much difference? The right diamonds only difference was .10 gr more of powder charge with same seating depth as top left diamond. Haven't had a chance yet to see if that neat little 3/8" group will repeat.....I won't hold my breath.

 

[ppoole]

Try to repeat it and try 4350. Do you have a chronograph?

 

[Deputy819]

Try to repeat it and try 4350. Do you have a chronograph?

Sure do. Numbers weren't that great with this last seating depth test. Powder was IMR 4451. Tried 4350 in this rifle already....groups AND numbers were awful. Best groups have been with RL19 and 4451, but not consistently. Gonna try and go a little slower with RL22 on my next OCW test whenever I can catch a break with the weather. Brass is prepped and ready to go.

 

[Rich Coyle]

Key word being HAD.....as in GOT RID OF...right?

Traded it for a handgun.

 

[Deputy819]

Gotcha. I'm not quite to that point......yet. So many dang variables to try and lock down.