300blk Bullet Seating Depth

[Yerman]

I am seating Hornady 150gr FMJ-BT tonight and ran into something a bit unexpected.

I trimmed my brass and seated the bullets according to Hornady 9th edition manual and the cannelure is not anywhere close to the case mouth. Is this normal?

[FLIGHT762]

Yes, it is normal because your bullet was not designed for use in the 300 black.

[___M|9||___]

thats correct because you need to remember that bullet was made for .308 and not 300 blackout. Flight762 is correct.

[Yerman]

Well that makes sense. Any thoughts on how the bullet will work in 300blk? Perhaps I should look for other bullets? I was looking at the Hornady 125gr SST and the Sierra 125gr HP Matchking.

I just loaded some 110 gr V-Max that came out really nice. Maybe I'll just stick with them. They also seem to be the least expensive.

[rg1]

For reloading for AR rifles and feeding from standard AR magazines the recommended overall length is 2.065" for the Hornady 150 FMJ. Overall lengths for the 110 V-max most recommended is 2.040". Doesn't look like you have the necessary one caliber at least inside the case neck which would be .308" inside the neck (not counting boat tail). Getting into the Blackout myself I read the best method to seat bullets for AR magazines is to measure on the ogive of a bullet and mark where the diameter is .250". Seat the bullets to where the .250" mark on the bullet lines up with the inside hump of the magazine. This corresponds to the normal diameter of a .223 round where it touches that hump. This method will insure rounds feed from the mags and straight into the chamber. For a bolt action or single shot Blackout you can seat to whatever length needed for chambering.

[___M|9||___]

it will work fine, just dont let the cannulere bug you, it was made for .308, just load, shoot and have fun!

[mu9en]

I have the same setup. But for me 2.200 feeds better in my rifle. I made a few "dummies" without powder and primer to see how it'll feed. 2.200 worked best for me. Yours may be different.

[Bigtls1]

I run mine to the cannelure with 16gr of H110. I don't remember the exact OAL off the top of my head, but I believe its 2.060.
That round shoots sub moa out of my AR.