AR15 in 30-30 via the 30HRT (150g bullet load workup)

[R.W.Dale]

I thought I'd make a quick post to share my chrony results from beginning load workup on 30HRT  shooting 150 grain remington RN bullets. I've posted this elsewhere but I figure the more hunting oriented membership here will dig this as well.

 For those not in the know .30HRT or herrett tactical rimless
is simply a 30Herrett formed on a 6.8spc case instead of 30-30wcf


Cases; Formed Hornady 6.8spc
Primers; CCI#41
Propellant; H-335
C.O.L. xxx" or .020" off the rifling
Firearm; White Oak Precision 20" 30HRT upper
Temp; 95 degrees

I lost a couple data points on the first two charges as my Jard trigger went out of adjustment and the rifle started doubling So I single fed rounds for the last two strings.

6-9-2010

27.0g 2120 FPS no accuracy data

28.0g 2230 FPS no accuracy data

28.5g 2237 FPS 5shots @100 2.2"

29.0g 2269 FPS 5shots @100 2.07"

6-10-2010 (trigger fixed)

29.5g 2329 FPS 5shots @100 2.2"

30.0g 2364 FPS 5shots @100 3.27"


 As it currently stands this load will equal what every 20" 30-30 I've owned will do with 150g bullets. Next I'll play around with COL and see if I can't better the accuracy of these loads.

 Looks like 29.5 grains will be the MAX due to a couple reasons, notably the accuracy drop off and bullet pushback after seating such a compressed load. Brass appearance with all loads was good with ejection at 4 to 5 o-clock appx 5 to 7 feet out

the ammo

the rifle

[Cheesehead]

I have a 6.8, so this is interesting stuff for me.

Cheese

[billy_56081]

Have ya tried ballitic tips this looks like a great app for them.

[30hrrtt]

Remington has introduced a similar round.  It's called a Remington 30 AR.

It's interesting to me because I've began playing with 150's in my 30 herrett.

[R.W.Dale]

Other than the bullet diameter the new Remington round really has nothing in common with the HRT. Introduced two years ago the 30RAR is sill pretty much vaporware. Leave it to Remington.


I just got done testing with the 125g ballistic tip and it looks like they're simply too long to work and still retain a usable case capacity.

[Dezynco]

Interesting cartridge for sure.  I love wildcatting, but if someone offered a 7.62x39 AR barrel with .308 bore, you would have a similar cartridge.  The problem with most (that I've seen) barrels in 7.62x39 is the .310-.311 bore that severely limits the flexibility of the cartridge.

[R.W.Dale]

Interesting cartridge for sure.  I love wildcatting, but if someone offered a 7.62x39 AR barrel with .308 bore, you would have a similar cartridge.  The problem with most (that I've seen) barrels in 7.62x39 is the .310-.311 bore that severely limits the flexibility of the cartridge.

You would I agree, however having experimented with both cartridges in the AR15 I've found there are several other distinct advantages the HRT has over 7.62x39

Superior magazines that actually work- 7.62 mags are a utter crapshoot

A much stronger bolt- because of the smaller case head (x39 AR's are notorious for breaking bolts)

much improved feeding characteristics- because of the reduced case taper

a much more pronounced shoulder- resulting in more positive headspace

and probably biggest of all a far far better case to work with- Hornady 6.8 cases have proven to be extremely consistent and strong. Compared to 7.62x39 cases which are too weak to support pressures beyond SAAMI spec and are worn out after 3 max loads (large primed)  or the defunct small primed rem cases that varied by over 10 grains in a single lot. I never did find a 7.62x39 case that would allow me to get within much under 200 FPS of the velocity figures I'm getting out of this HRT

[Lloyd Smale]

I have to agree with you that the 762x39 can be a little bit finiky. The c products mags cure the mag problem. What ive come to do is buy cproducts mags and replace the mag spring with a wolf extra power AK mag spring and they run flawlusly like that.  ive shot a couple cases of wolf along with a few thousand rounds of reloads through mine with absolutely no problems now. The bolt problem can be cured with an aftermarked bolt. I called bushmaster (mine is one) and they said they allready upgraded the bolts in there rifles and have had no trouble. Im curious as to the differnces in case capacitys of the two. One big advantage i see in the 762x39 and the reason i bought mine is ammo availabilty. When the shortages hit i could still buy it and its cheaper then about anything else and i also like the fact i can grab it take it to camp and shoot up a few hundred rounds and not even have to worry about crawling around on my hands and knees looking for brass. Im not a big fan of wolf ammo but thats one advantage it has. Granted though i can only get what your getting using 130s and feel comfortable with it. nice thing is that 130 vmaxes shoot into an inch or less at a hundred and wolf will even group under 2 inch.

[Dezynco]

Let us know more as you progress.  I recently built an AR15 in 300 "Fireball"  aka 300-221.  I ordered the barrel from Model 1 Sales.  No problems at all so far, and the more I shoot, the better it groups at 100 yards!  I'm actually shooting a touch over 1" - 5 shot groups, and that's with a stubby little 16" barrel.  I'll bet your groups will improve with more shooting, cleaning, shooting at the barrel settles in.  You might experiment with different powders also.

What is the rifling twist on your 30HRT?

[R.W.Dale]

The 7.62x39 mags I had were c-products  10 rounders that would choke if more than 6 were loaded

As to the bolt breakage it appears as though it doesn't matter who'se bolt you run. Folks over on AR15.com have even broken the LMT superbolts

All in all these advantages add up to an AR that runs better, hits harder and is much more accurate.

[R.W.Dale]

Let us know more as you progress.  I recently built an AR15 in 300 "Fireball"  aka 300-221.  I ordered the barrel from Model 1 Sales.  No problems at all so far, and the more I shoot, the better it groups at 100 yards!  I'm actually shooting a touch over 1" - 5 shot groups, and that's with a stubby little 16" barrel.  I'll bet your groups will improve with more shooting, cleaning, shooting at the barrel settles in.  You might experiment with different powders also.

What is the rifling twist on your 30HRT?

I'm pretty satisfie with the accuracy of my other loads.

[Lloyd Smale]

my 762x39 shoots just under an inch for 5 shots at a 100 yards. Its a 16 inch gun too. It doesnt miss a  beat anymore. I had it out today and finished off the third case of wolf thats gone through it. no broken bolt yet and i guess even if i had to buy a new bolt every 5000 rounds its not much of a consern. I probably save enough money every 1000 rounds to buy one. the 762x39 doesnt take a back seat to any round when loaded with good bullets in a good gun. Its the case alot of bench rest rounds are  based on. Mine is everybit as accurate and reliable as my buddys 6.8 and i can actually find ammo and brass for it. Something that cant be said about most of the other guns mentioned. I love my beowulf too but finding brass and bullets is a full time job if you want to shoot it much. Personaly i dont want to put up with those headaches to get the small advantage those rounds offer over the 762x39.

[Dezynco]

I thought very seriously about ordering a 7.62x39 barrel, but I wanted to "fiddle" with the 300 Fireball.  No regrets, but the 7.62x39 is one of my favorite cartridges.  It was a little cheaper to build the 300 Fireball too since the standard magazines and bolts work.  Haven't totaled it up, but the cost of the 300/221 reloading dies may have offset the extra $$ for a bolt and magazine for the 7.62x39!

The 30HRT certainly looks promising for those of us who like to mess around with things!