Hey y'all, I'm new to hand loading, bought my first rifle, an Ar-10 last year, been researching a lot about precision hand loading, and I'm wondering if there is a bullet seating depth process for semi-auto's? Obviously the magazine will only load a certain overall length, which I've found to be a little longer than the saami spec for my cartridge, and bullet weight.. I don't know the difference in barrel engineering from a bolt action to a semi, or if there is any, and if there is, how much space, and take up can there be had. I'm not looking to compete, this is an all purpose rifle for me for self defense, and long range hunting of which I'm looking for accuracy for. Somebody give me the explanation for either or, thanks.
Bullet seating depth for AR's?
- Thread starter G19Kev
- Start date
Obviously you will be limited by magazine length. As to what your particular barrel will shoot best with is unique to it. In general start with the COAL that is suggested by your bullet manufacturer or what they use for their own cartridges. If that length didn't work in a large variety of guns they wouldn't use it.
AR10 as in an Armalite rifle or simply a large frame AR (LMT/KAC, etc)?
What bullet will you be using?
What magazine (KAC or Magpul)?
If running the 175 smk, seat the bullet such that the base to ogive (BTO) is in the range of 2.120”-2.150”. This should yield an OAL in the range of 2.800-2.830”. The final BTO number will be driven by space in the magazine and whatever seating depth the rifle likes within that general range if less than the available internal mag length.
If you don’t know what BTO is or how to measure it, you can consult YouTube.
What bullet will you be using?
What magazine (KAC or Magpul)?
If running the 175 smk, seat the bullet such that the base to ogive (BTO) is in the range of 2.120”-2.150”. This should yield an OAL in the range of 2.800-2.830”. The final BTO number will be driven by space in the magazine and whatever seating depth the rifle likes within that general range if less than the available internal mag length.
If you don’t know what BTO is or how to measure it, you can consult YouTube.
I have a Daniel Defense DD5 V5 6.5cm, and I want to use the Nosler 142g ABLR. I see what your saying... Don't go by OAL, because anything above the ogive doesn't touch anything in the chamber. Got it, but there is no way, or tool, to measure the chamber on a semi-auto, like they do on a bolt action?
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You can use the straight tool with the bcg removed. The curved tool is for lever guns where the ejection port is your only way to access the chamber.
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