.30 Remington AR

Vince · Posted: Mon Nov 04, 2013 7:12 am Post subject: Re: .30 Remington AR

slimjim wrote:

Vince wrote:

I now have an old .303 barrel that is in good condition, and that should be suitable to build something around.

Vince, what is it's twist rate?

Not sure Slim...I haven't measured it yet. The actual idea is still in its early stages, so I am not entirely sure which way I will go yet. I might even get a length of barrel made, although that usually works out quite expensive.

Another idea I have in the back of my mind is to make a "chamber insert" in .300 BLK for my 12g shotgun. That way I will most likely only have a barrel length of one full revolution of the lands.

As I say...only in it's infancy, and I am still not 100% sure what the finished product will actually be.

slimjim · Posted: Mon Nov 04, 2013 6:42 pm Post subject: Re: .30 Remington AR

Vince wrote:

Another idea I have in the back of my mind is to make a "chamber insert" in .300 BLK for my 12g shotgun.

How will you hit anything with that? Do you already have a scope on it?

slimjim · Posted: Mon Nov 04, 2013 6:47 pm Post subject: Re: .30 Remington AR

Wow, I didn't realize how overstablized a .308 bullet is with a 1:10 twist.

Here are a couple of useful websites. The first one is a stability calculator. The second is a bullet length database.

www.jbmballistics.com/...ab-5.1.cgi

www.jbmballistics.com/...gths.shtml

220gr Sierra MK 1.489"
220gr Round-nose 1.303" (name match with your barrel)

PaulS · Posted: Mon Nov 04, 2013 8:51 pm Post subject: Re: .30 Remington AR

My 03A3 has a 1:10 twist and it wouldn't stabilize a 220 grain bullet. they were hitting the target sideways at 100 yards.

slimjim · Posted: Mon Nov 04, 2013 9:09 pm Post subject: Re: .30 Remington AR

The bullet manufacturers use a more sophisticated stability equation than we have in using the Greenhills equation. Once you get much below 1.25 its a roll of the dice. I've had some at 1.1 do fine and other not hit the paper at 50 yards. Always check the coldest temp you hunt in. Stability decreases as the air gets colder/denser.

gelandangan · Posted: Mon Nov 04, 2013 9:10 pm Post subject: Re: .30 Remington AR

This thread is getting awesome..

A few years ago when i want to build a 300 Whisper I was plenty discouraged, but now that the 300 BLK gets SAAMI rating, it actually flourish and get many followers...
YEAH.. BLOOOMPH Rules!!

1:10 would stabilize up to 220 grains Ok at 2500 fps.
at subsonic, it is not as good, but it is also determined by the boolit shape. flat squat boolits can be easier stabilized than the ones with long ogive.
But then again the plus sides are, with subsonic velocity loads, you would not be inclined to hunt beyond 100 meters, and tumbling are great for hunting purposes, it kills quickly by opening the wound channel without need to mushroom.

Elvis · Posted: Tue Nov 05, 2013 12:43 am Post subject: Re: .30 Remington AR

so what (other than its newer) is the advantage over a x39???
which you could use your barrel for Vince. and if your barrel is thick enough at chamber end you could easy make a chamber insert and still leave barrel longish just need a rubber washer? maybe to hold it still bit shouldnt need that as chamber bit should centre it nicely.

slimjim · Posted: Wed Nov 27, 2013 12:04 pm Post subject: Re: .30 Remington AR

Pkslinger, I found this article in Hodgdon's 2011 Annual Issue of the Reloading Magazine. I thought it had some good info in it on the 30 AR. BTW, I'm loving my 6.8mm SPC II. Parts and component availability has been there when I need them. The 6.8 has plenty of good bullets designed for it and is effective with 16" barrels making for a light, easy handling rifle. Shot a doe with it at 200 yards last month.

Hope you enjoy the 30 AR article.

slimjim · Posted: Wed Nov 27, 2013 12:05 pm Post subject: Re: .30 Remington AR

Page 2

slimjim · Posted: Wed Nov 27, 2013 12:06 pm Post subject: Re: .30 Remington AR

Page 3

slimjim · Posted: Wed Nov 27, 2013 12:29 pm Post subject: Re: .30 Remington AR

Page 4

slimjim · Posted: Wed Nov 27, 2013 12:31 pm Post subject: Re: .30 Remington AR

Page 5

slimjim · Posted: Wed Nov 27, 2013 12:32 pm Post subject: Re: .30 Remington AR

Page 6

slimjim · Posted: Wed Nov 27, 2013 12:33 pm Post subject: Re: .30 Remington AR

Page 7

slimjim · Posted: Wed Nov 27, 2013 12:34 pm Post subject: Re: .30 Remington AR

Page 8 (sorry for the distortion)