changing trim lenghts

[Backr]

i have a question just out of general curiosity, i have a box of new .308 lapua brass, i resized them all, and every case is at 2.008 but for 5 cases they are at 2.006.

now if i develop a load with the case lenght at 2.008, and then hypothetically decide after once firing to trim all the cases down to 2.005 (hornady recommended) to utilize the other 5 cases.

will there be a accuracy difference and/or need to redevelope the loads, or should this not make a difference?

i ask because i ordered a new case trimmer and it doesnt come in till next week, i happen to have a 4 day weekend which would allow me to get in some range time to test the loads.

 

[Engineering101]

That small of a difference in case length won't be an issue. While it is important to have every round the same as much as possible to achieve best accuracy some things make more difference than others. Other things to consider in the neck area are concentricity and annealing your brass every few shots. When I started dealing with those things in particular I found I stopped having flyers.

 

[Backr]

Thanks for the information, I didn't want to find a great load, trim the cases farther down and suddenly having bad groups, do you send your brass off to get annealed or self taught?

 

[gohring3006]

Depending on the trimmer you have coming. It will have that much or more variance with in its design. Only a few on the market have less than that...

 

[Engineering101]

Backr

Guns are a hobby for me so I do most things myself. I have an annealing setup that works well with an inverted drill press to spin the brass and a 5 gallon propane tank feeding a hand held torch. There are good write-ups on how to anneal brass out on the web. If I recall, and sometimes I don't, Accurate Shooter had some good info.

 

[Rich Coyle]

If you chamfer them you will introduce more variation than .002" on the contacting surfaces..

 

[Backr]

Depending on the trimmer you have coming. It will have that much or more variance with in its design. Only a few on the market have less than that...

Gold point, I had a rcbs but it was scuffing the inner necks to much for my liking, so I ordered a wilson

 

[Backr]

Backr

Guns are a hobby for me so I do most things myself. I have an annealing setup that works well with an inverted drill press to spin the brass and a 5 gallon propane tank feeding a hand held torch. There are good write-ups on how to anneal brass out on the web. If I recall, and sometimes I don't, Accurate Shooter had some good info.

That's really interesting, I am definitely going to look into that. My wife is 8.5 months pregnant so I probally won't have time to start doing this myself for a while here but definitely something I'd like to learn how to do.

 

[tbrice23]

That's really interesting, I am definitely going to look into that. My wife is 8.5 months pregnant so I probally won't have time to start doing this myself for a while here but definitely something I'd like to learn how to do.

Man oh man, your reloading career is .5 month from being over.

 

[Backr]

yeah pretty much lol, thats why im hoping to get 3 good loads worked up before then, so come hunting season i need to do minimal adjustments. loaded up some 175smk, some 165 partitions and some 180 interbond bthp, so we shall see how they fly, so far this rifle has been putting factory ammo well under an inch so i cant complain.

 

[tbrice23]

Imr 4064, varget, RL15, even imr4895 will be good powders to try.

 

[Backr]

Sweet thanks, I loaded these up with varget since I have a lot of it, I might try some rld 15 as well, I'm hoping to get out to the range early this week so I'll snap some pictures of how they shoot