Brass Exclusive To Each Rifle?

[WinJim1863]

I shoot 6.5 CM and now have two rifles in that caliber- Tikka T3x TAC and Christiansen Arms BA Tactical. I full length size and have planned to use the same brass (Lapua) in each rifle. Now I am questioning that. I check concentricity (at ogive) after each loading. I have been down to averaging < .001 on some loadings (usually 50-80 rounds depending on match) and always average under 0.0014. I have been pleased with that but now its all gone sideways. On my last loading I averaged 0.0021- within that group however I had one at .005 and several at 3 to 4 thou.
The only thing i've changed in my reloading process is lube- I have gone to lanolin from Frankford Arsenal pump spray- can't imagine that would explain it.
Could the problem be that I am now using the same brass in both rifles? The chambers in the two are very different- CA very tight chamber, Tikka very long throat. I have felt that with full length sizing that wasn't the problem but maybe Im wrong. The CA is pretty new as is the brass so the runout problem started about the time I began using same brass in both rifles.
I will appreciate any advice and help,
Thanks, Jim

Sorry, think I posted this in the wrong bucket

 

[hlee]

Do you know run out is a problem? I mean, are you seeing a degradation in precision, or groups that are below an acceptable threshold? Are you able to hit the targets you are aiming at? I think that reloaders sometimes fall into rabbit holes that are academic and not practical. If it were me, unless I had determined that run out was actually causing a problem, I wouldn't worry about it...

 

[RTH1800]

I use designated brass for my precision rifles and on AR's I use it in any of them. I only load it 2-3 times for AR's.

 

[WinJim1863]

Do you know run out is a problem? I mean, are you seeing a degradation in precision, or groups that are below an acceptable threshold? Are you able to hit the targets you are aiming at? I think that reloaders sometimes fall into rabbit holes that are academic and not practical. If it were me, unless I had determined that run out was actually causing a problem, I wouldn't worry about it...

HLee,
I haven't shot the latest loading yet. Ive marked the worst rounds but it is hard to know at 600 yards where each round hits.
What I know about myself is that if I have confidence in my load I shoot better. Also I respect Brian Litz and he says there is value in paying attention to runout.
On my last outing at 600 with ammo I felt good about of 20 rounds I had 15 in the 10 ring (9 in the X ring), 4 in 9 ring and one in 7. Now, frankly, that's the best Ive ever done (I'm only a year into smokeless powder/mid range). Based on that Ive felt that I was doing a good job of paying attention to the little stuff and had the results that confirmed that. Now somehow I've managed to screw it up.

 

[antithesis]

Concentricity out of the rifle is where you find if the chambers are doing stuff with the brass. Concentricity after your loading process is where you find out if you are doing stuff with your brass.

The numbers you are using are very small, almost like you have an extra zero in them. If they are the right numbers then I don't think you have anything to be concerned about.

Are you annealing after every firing? If not, consider it. And yes, the lube can change things. You want the minimal amount of the thinnest lube needed to get the job done. The FA stuff is pretty thick. Grab a can of Imperial - stupid thin, a dab is enough to lube around 5 cases with just a quick spin between your fingers, and it wipes of with a cloth.

 

[demolitionman]

I use designated brass for my precision rifles and on AR's I use it in any of them. I only load it 2-3 times for AR's.

Hey rth, do you find you have to trim every other firing and sometimes every firing on your ARs? I’ll go 3 or 4 reloads before trimming bolt gun brass. Sorry for the thread derail.

All my bolt guns have exclusive brass that only gets used in that rifle.

 

[RTH1800]

I don’t trim AR brass. I use a bushing die and don’t use expander ball. If it gets long I get rid of it. I have a very large supply of .223 brass and only shoot 4K or so per year.

 

[AIAW]

Using bolt-action rifles as an example: The problem I've had (and it will vary from chambering to chambering) is the case web expansion. Depending on the barrel, degree of expansion and brass quality it's possible to NOT be able to chamber brass in a different rifle.

For instance as a test I tried... 308 brass fired in my AW will not chamber in my AXSA. Same goes for 338LM brass fired from the AXMC - won't chamber in my Sako M10. Can't small-base 338LM brass (too thick), so that brass now has it's dedicated chamber selected by force.

Moral of the story basically: Buy or make a small-base die for your brass, or risk being forced into using it in the same rifle. I have no problem with running the same caliber brass in different chambers, but I don't (in bolt guns specifically). It just makes clear sense to keep that brass with that rifle/barrel after it's fire-formed.

 

[Jammer Six]

I think that reloaders sometimes fall into rabbit holes that are academic and not practical. If it were me, unless I had determined that run out was actually causing a problem, I wouldn't worry about it...

AMEN!

Coming from a competition pistol background, it appears to me that benchrest guys seem particularly susceptible to things that don't matter. It's almost like listening to superstitions sometimes.

What matters is the holes in the target.

Adding standard deviation to the readouts on chronographs was the work of a cruel, vicious sadist.

A genius, and extremely subtle, but completely evil and inhumanly cruel.

 

[kujuak]

Given the cost of the rifles, barrels, bullets, gas to get to range, time to reload I decided in the long run to get 2 dies and use 2 sets of brass for my two 308 precision rifles and use my 30 year old standard 308 dies for my other 308 rifles.To make it even simpler I am using Palma 308 in one rifle and standard Lapua in the other. I have a load with 185 Juggernauts and Varget that shoots better than I can hold and is temperature stable.
Works fine for me so far.

 

[Milo 2.5]

Concentricity out of the rifle is where you find if the chambers are doing stuff with the brass. Concentricity after your loading process is where you find out if you are doing stuff with your brass.

Pay attn to what this guy just said. If you think one of the rifles is causing the issue, isolate it.
Another guy mentioned chamber dimensions, esp dia of the fired cases from each rifle, if they appear to be close most likely it will be a non issue, you can make this work. Yes, in a perfect world you would have 2 batches of brass and 2 sets of dies.
If it was me, I would find out if it is a chamber causing this, or your practices. Concentricity of brass should be in it's truest form coming from your chamber(fired).

Now, I am not badmouthing your rifles, but honestly, do you think either the Tikka or the CA will be able to shoot the .001" diff in your readings, given the fact that .002" is not a bad number at all?