brass: how much does it impact accuracy?

[Bigeclipse]

I do know that changing brass can impact accuracy but I wanted to hear if anyone has had to do this and what they have noted for accuracy change. The reason I ask is I have a couple loads worked up for rifles using factory remington brass that I got at the range. I am having a hard time finding remington brass and I am thinking about going to another brand. For a 500 yard rifle how critical is this? Will I need to work up a whole new load or will I mostly see maybe a change of say .3moa...I read an article once which had a guy using several types of brass but everything else was same such as powder primerd and seating depths and although accuracy did change it was not much...from worst being .7moa and best being .3 MOA. Yes I understand that is significant to some but for a 500 yard rifle I'd think that would be ok as long as my rifles were still below 1 MOA. Thoughts?

 

[Greyfox]

For the shooting requirements you describe changing brass should not be a big deal. The biggest factor will be the case capacity differences between brands. I have found 1-2 grain difference between brass brands in 308 sized cases. This might require reducing your charge if your new case has a lower capacity and your current load is at max pressure. I will generally compare net weights(with either water or powder) between my current case when fully filled to the sized current brass and compare it to the new brass. Subtract the weight of the empty cases from you weight since the raw brass will likely have weight differences. Winchester brass has been generally thinner than Remington brass and has larger capacity. If Im running stiff loads and my new brass has a lower capacity, I will usually back off a grain or two when trying loads.

 

[Deleted member 46119]

In my rifles and for me. I have different loads for different brands of brass.
so
Yes, different brass can have an impact greater than my tolerance.

Each rifle is different+caliber+load is different in it's tolerance. Example: I have 2 loads for my 260 that I can use for matches. Slow: Nosler brass, ~42gn H4350, 140 A-Max. Fast: Lapua brass, ~44gn H4350, 140 A-Max. If I try to run the Lapua brass slow it doesn't work as well.

Mostly it's down to case capacity and the effect on velocity. If you can measure fired brass of each brand and develop a formula of adjustment.

Hope that helps.

 

[Bigeclipse]

In my rifles and for me. I have different loads for different brands of brass.
so
Yes, different brass can have an impact greater than my tolerance.

Each rifle is different+caliber+load is different in it's tolerance. Example: I have 2 loads for my 260 that I can use for matches. Slow: Nosler brass, ~42gn H4350, 140 A-Max. Fast: Lapua brass, ~44gn H4350, 140 A-Max. If I try to run the Lapua brass slow it doesn't work as well.

Mostly it's down to case capacity and the effect on velocity. If you can measure fired brass of each brand and develop a formula of adjustment.

Hope that helps.

I should have also mentioned this is for minute of deer as well and not target shooting. I have decided that for 500 yards I like my rifles to hold about .75MOA. My current rifle which I'm thinking of changing brass is right around .6moa mark. So from what it sounds is yes the brass can change my accuracy but do you think I should be able to fine tune my load with the new brass by changing the powder a little bit and seating test or are you saying I will have to do another full blown ladder test and start over?

 

[Deleted member 46119]

I should have also mentioned this is for minute of deer as well and not target shooting. I have decided that for 500 yards I like my rifles to hold about .75MOA. My current rifle which I'm thinking of changing brass is right around .6moa mark. So from what it sounds is yes the brass can change my accuracy but do you think I should be able to fine tune my load with the new brass by changing the powder a little bit and seating test or are you saying I will have to do another full blown ladder test and start over?

IIWM: Change the powder charge a little. Don't change the seating.

It should only be a few .1 either way.

 

[johnnyk]

I think the capacities variance of the different brass changes the pressures of the given load, which affects your barrel harmonics, velocity and POI. This, at long range is a deal breaker.

Last weekend I was working up a load for a friends Remington .223 heavy barrel. I was using the same bullets (52gn SMK), primers and powder, but Hornady and Remington brass. Using the same point of aim, the Remington loads printed 1/2 an inch higher than the Hornady's. This was a mild load (23.0gn of Viht N133), imagine what a hot rod magnum load, near max pressure, would do.

I think this is where the recommendations to sort your brass, in headstamp and weight, comes from. Just my $ .02 worth. JohnnyK.

 

[rooster721]

Brass is everything in my opinion (regardless of distance) if accuracy and consistency is what you want... I myself have seen very-dramatic changes in accuracy plainly related to brass alone. Flyers and inconsistency has driven me bonkers the last number of years and I've taken it upon myself to understand *** a guy has to do to eliminate the frustration best he can... I am (ironically-enuf) finishing up my-own tests, measuring the differences consistent brass and the run-out (in-it) alone (and in its loaded rounds) make.

So far, in one of the calibers, I've noted plain-jane minimal prepped brass without any annealing or neck-turning or flash-hole de-burring (basically nothing but, size/trim/chamfer) ...a guy will see lets say a 1.75' group in "a finished load"

...same finished load in brass with a full prep job (anneal/size/trim/chamfer/flash-hole deburr AND neckturn) you may see a shrink to 1.0" maybe less

...same exact load AGAIN, only with that full-prep brass yet sorted for run-out to be (my-case I been going +/- 3thou and less as my special-select stuff) ..and that 1.0" group can be cut by another 1/4"-3/8" !!! based on what I've seen in my firebird AND so-far as I am finishing up my 338 tests* Groups and their consistency have shrunk in an almost unbelieveable size, and best of all the flyers that I could never figure out have basically disapeared... and my groups are as they should have been all along

So, in a nut-shell (and in my-own firm opinion) yes-absolutely... brass of different make, lot and prep-level without-a-doubt does impact accuracy

 

[Bigeclipse]

Brass is everything in my opinion (regardless of distance) if accuracy and consistency is what you want... I myself have seen very-dramatic changes in accuracy plainly related to brass alone. Flyers and inconsistency has driven me bonkers the last number of years and I've taken it upon myself to understand *** a guy has to - 3thou and less as my special-select stuff) ..and that 1.0" group can be cut by another 1/4"-3/8" !!! based on what I've seen in my firebird AND so-far as I am finishing up my 338 tests* Groups and their consistency have shrunk in an almost unbelieveable size, and best of all the flyers that I could never figure out have basically disapeared... and my groups are as they should have been all along

So, in a nut-shell (and in my-own firm opinion) yes-absolutely... brass of different make, lot and prep-level without-a-doubt does impact accuracy

Thanks for the info. I am by no means a long range hunter but I am slowly working my way up. The goal for this year was simply 300 yards on deer and 400 on paper. This winter and summer I want to bang steel out to 500 and depending on my confidence take a shot on a deer next winter at 500. This is my absolute max distance I can hunt without traveling and I won't be traveling for at least a few years so I am trying to work up loads that are sub MOA out to 500. Half MOA would be ideal. My 7mm rem mag does this no problem out to 400 without any brass prep except for resizing and trimming. Maybe that means it should be shooting even better haha. My other rifle is definitely a bit more picky. My best load hovers right around .8moa right now out to 400. I need more brass for it and can only find lapua or hornady. My loads were worked up using remington brass so I was wondering what the impact would be when I switch brass if this meant a full load work up again OR a simple powder grain tune on my current load

 

[Dr. Vette]

My 7mm rem mag loads were worked up using remington brass so I was wondering what the impact would be when I switch brass

Is it really that difficult to find Remington brand 7mm RM brass?
I see a lot of it on Gunbroker - even once used brass is going to be better than starting over with a different brand.

Trim it, square the primer pockets, clean up the flash hole and then check the neck thickness. Sort them out to find the best brass and you're ready to go.

 

[johnnyk]

BigEclipse,
If I were in your shoes, I would abandon my current Remington load, start over and build loads with Lapua brass. Much, much better stuff. I shoot it for my 6.5-284 Norma and can only wish other brass were as good and consistent as Lapua.
I have heard mixed reviews about Hornady but I would love to give it a try. Last year I started using Frontier brass for my .300WinMag and got about 6 loadings from it before the primer pockets got too big. These were all high end loads though but the brass did produce some fine accuracy while it lasted.
I have regressed back to some "back-up" Remington brass. Even though it's new, prepped and annealed, I still got an almost complete head separation a week ago.

"Brass is the fountain from which all accuracy flows." Jim Carmichel

JohnnyK.

 

[Dr. Vette]

BigEclipse,
If I were in your shoes, I would abandon my current Remington load, start over and build loads with Lapua brass. Much, much better stuff. I shoot it for my 6.5-284 Norma and can only wish other brass were as good and consistent as Lapua.

JohnnyK.

Great idea - if only Lapua made 7mm Rem Mag brass. They do not make any belted (magnum) brass, only beltless.

If I were you and were going to switch brands of brass, when it becomes available I would buy 200 pieces of Nosler brass in 7mm Rem Mag and be set for a long time.

Nosler Custom 7mm Remington Magnum Brass 50 Count Box

Watch the Shooter's Pro Shop site for blem brass or overruns that will save you some money on it as well.

I find that it takes hours to "fix" Remington, Winchester, Federal or Hornady brass to match what you can buy right away from Nosler or otherwise Norma. However, the Nosler seems to be a bit less expensive and gets better reviews so I would go that way first.

If you can't wait to buy the Nosler then I'd pick up some once fired brass, prep it and cull out the ones you don't like, and go from there.

 

[Gunpoor]

I have tried changing brass a few times without changing the load and what I have found is sometimes the difference in accuracy is minimal and other times it is horrible. I would advise you to work up your load with the brand of brass you will be shooting. With pistol cartridges I don't worry about the headstamp, but with rifle loads I don't mix, except for my TC Contender carbine chambered for 30/30win; it doesn't seem to matter what is used and still shoots sub MOA.

 

[Bigeclipse]

Is it really that difficult to find Remington brand 7mm RM brass?
I see a lot of it on Gunbroker - even once used brass is going to be better than starting over with a different brand.

Trim it, square the primer pockets, clean up the flash hole and then check the neck thickness. Sort them out to find the best brass and you're ready to go.

lol actually I need it for my 3006 but yes...I have not been able to find any at gun shops around me.

 

[Bigeclipse]

Great idea - if only Lapua made 7mm Rem Mag brass. They do not make any belted (magnum) brass, only beltless.

If I were you and were going to switch brands of brass, when it becomes available I would buy 200 pieces of Nosler brass in 7mm Rem Mag and be set for a long time.



If you can't wait to buy the Nosler then I'd pick up some once fired brass, prep it and cull out the ones you don't like, and go from there.

One more question, I have never used brand new brass...always spent brass I got for free from our range. I have read you should fire form your new brass which means shooting all new brass. That seems awfully expensive and a waste. Is there anything you can do during the fire forming process that will at least benefit working up your load or does first firing need to be done with lower charges...etc.