brass prep

[digerup]

Has anyone tried comparing prepped brass accuracy to non prepped. As long as case length is within specs, how much will accuracy suffer. I am waiting for a calm day to try this out. My current 5.56 load with prepped brass is about .75". I am going to try loading without trimming and primer pocket cleaning. Let me know if you have tried this.

[PKT1106]

Over on the benchrest forums and even Snipers Hide, this is a topic that has been discussed many times. Comparing "prepped" cases to "non-prepped" cases, I assume you are saying that the "un-prepped" cases will be resized, checked to make sure they are not over max length and, if OK, loaded as is.

How are you going to resize? Full length vs neck-only? If you are looking for the lowest possible group size, not trimming can lead to variations in the case length and can affect seating depth, especially when using canalured bullets. In this case, you would have to sort out cases by length to control that variation.

Bottom line is, if you are looking to get the absolute tightest group you can, you should make sure all your brass is uniform, weather you trim everything to length or sort un-trimmed brass by length.

[digerup]

I full length size for AR platforms. For my bolt actions neck size only. I've noticed after trimming cases they stay pretty uniform after firing once or twice. I will test this out when I get a day w/o much wind. If I go from .75 to 1" groups not sure it will really matter in a match.

[Aaron M]

Really at 100 yards you are probably not going to see much of a difference if you are using good bullets and a consistent reloading method. Where you will see the difference in accuracy is at longer distances 600 yds+.

The type of prep that you are doing i.e(Trimming/cleaning primer pockets) will not really affect you accuracy that much anyway it is more of a general maintenance that makes reloading easier and safer. The main thing I would stress with accuracy is consistency in your prep and reloading practices.

Brass prep that will increase accuracy: Weigh cases and shoot cases within a couple tenths of a grain with each other, uniform your primer pockets to start out so you are consistently seating your primers to the same depth, if you have a flash hole deburring tool cut the burr out of the inside of the flash hole that the punch left so you have uniform ignition....I could go on....

Edited May 7, 2012 by Aaron M

[digerup]

Did a little testing last week. Shot about 20 rounds each prepped and non prepped. There was no noticeable difference in groups at 100yds. For matches I would still use prepped brass for more confidence with reliability, but practice looks like it works fine.

[ben b.]

I'm going to hazard a prediction: Eventually you will get bitten by not trimming your AR brass. Either reliability problems (fail to return to battery/extraction problmes) or a blown case head.

[JACKIE40X40]

Ben is dead on, case prep is important. Not just for accuracy,for dependability. A case failure and your most likely your out. Not saying that it can't happend to if you

Use precision technics.