Max bullet length for AR?

[Lonewolf74]

I'm looking for some different bullets to play around with in my AR. It's a 7 twist barrel so I can stabilize long heavier pills but the restriction is mag length.

So I was wondering what are the longest bullets you guy's have been able to use?

Can I use some 70+ gr vld's or smk's?

 

[philipbrousseau]

sierra says 7&8 twist will stabilize 80 gr matchking. 90gr m.k. needs 6.5 twist. i've not used vld's in my ar. 69gr match king is longest i've tried. i'm sure others on here can answer for the vld's.

 

[el matador]

Its not so much the length of the bullet you need to worry about, but the length of the ogive. Anything shorter than .500" will work without issues and you may be able to fudge another .050 or so. Much longer than that and you'll be seating the ogive down into the neck.

I have used Hornady 75 grain BTHPs and they work fine. Most bullets in the 68-70 grain range will also work well. The 75 grain A-Max is too long (ogive is about .585"). I loaded some of these for my AR but had to single feed them. I pulled some of the polymer tips out with pliers, leaving a hole in the tip, so I refer to them as A - Hole - Max bullets.

Here is a sheet that Len posted a while back with measurements for Berger bullets: http://www.longrangehunting.com/forums/f19/berger-bullets-tech-data-list-39871/
You can calculate the ogive length by subtracting "base to ogive" from overall length. Looks like most of the heavy Bergers are too long to work in an AR with the exception of the 77 grain OTM.

 

[rcoody]

I'm looking for some different bullets to play around with in my AR. It's a 7 twist barrel so I can stabilize long heavier pills but the restriction is mag length.

So I was wondering what are the longest bullets you guy's have been able to use?

Can I use some 70+ gr vld's or smk's?

69 gr Sierra MK is my favorite

COL of 2.26

24.7 gr CFE223

VLDs like a jam. Need a bobsled and single load them

 

[Lonewolf74]

The 69 or 77 grain Sierra mk's are what I have been leaning towards just not sure which to choose. I've been messing around with Hornady 68 gr bthp which I think is pretty similar to the 69 smk and I can't get them to shoot that great.

Have you used the 69 SMK's on any coyote's? They alright for smaller animal's like such?