poor mans 300 whisper/blackout

[Jason F]

220 hornady rn loaded in 30 carbine handi rifle.  Loaded at 1.9 just at rifling. Wonder how much unique i can get in there safely.

[R.W.Dale]

Not unique use TRAIL BOSS

As long as you don't compress it its impossible to go overpressure

[Jason F]

I got some trail boss.  Gonna give that a try to.

[R.W.Dale]

If you really want to pursue this I would rent a throating reamer and extend your leade far enough to have one worth caliber of bullet shank in the case at the lands.

Just looking at the pic this would double your usable case capacity

[bikerbeans]

Jason,
 
I'd take a 1/4" diameter, 24" brass rod and mallet with me to the range.  Driving out a stuck jacketed 30 cal bullet requires a bit of hammering.    Voice of experience here.
 
BB
 
Link so you can check the minimum velocity you need to stabilize the 220 grainer.
 
      http://www.jbmballistics.com/cgi-bin/jbmstab-5.1.cgi

[Jason F]

Jbm ballistics calculator says 1100 fps will stabilize. Do you think there is enough case capacity left to get it to 1100?

[quickdtoo]

QL predicts 5.5gr 2400 will achieve 1000fps in an 18" barrel loaded to 1.9" COL, 26.2kpsi. The usual disclaimer really applies here, QL is notoriously inaccurate with small volume straight wall cases,  for example QL predicts published A1680 loads in the 357Maxi as being considerably more pressure than what they actually are, so I'd recommend using Trailboss with IMR load instructions and throating it, BB makes a good point too, what's the actual barrel length? I'd be most apprehensive in a longer barrel.

Tim

[Jason F]

Barrel is 21" long

[quickdtoo]

I'd throat it, right now the bullet is using over half the case capacity, it doesn't allow much room for error considering you're working in no man's land, it could work fine, then become a bomb with just a liitle more powder, one grain of powder increases pressure over 10k when there's so little volume. 

Tim

[bikerbeans]

Jason,
 
if you make a long throat on your carbine for a 220 grain bullet then you probably will not be happy with your accuracy if you go back to shooting regular M1 carbine bullets.
 
I would be nervous with your cartridge as is using Trail Boss.  Trail Boss is a low velocity powder, it isn't necessarily a low pressure powder, take a look at Hodgdon's website and look at their published pressure data for various loadings.  I used TB for my 308 chipshot with 190 grain .308 bullets and with less than 100% loading I had primers come out of the pocket.    The chipshot has 1/2 grain more capacity than a 7.62x39mm cartridge and that is a lot more room for powder than your 30 carbine @ 1.9" with a 220 grain RNs.  What ever you decide to shoot, if you do shoot it, I would use remote ignition and please do super-slo-mo video.  If there is an "event" you might be able to sell the video for enough $$$ to buy another carbine barrel.
 
BB

[Jason F]

I am not gonna try it, it shoots great the way it is so throating is out of the question.

[Jason F]

But i am gonna try my 30-30 with the 220 hornady rn subsonic . Then i am gonna load some barn burners in the 30-06 ultracomp with the same bullet,i got two boxes of them

[quickdtoo]

I don't blame ya for that decision Jason, it's just not worth it.  But throating with a good throater makes a tapered leade that is conducive to excellent accuracy, my 35 Rem and 405 Win both have em and both shoot one hole 100yds groups, it will likely require changing the load, but to say it can't shoot good after throating is a bunch of hooey IMO, the requirement to be able to reach the lands for good accuracy is also bogus. 

Tim

[R.W.Dale]

Look at it this way. Even if accuracy suffers with 110g bullets you've traded using the least accurate most worthless 30cal projectiles mankind has yet devised  for use of the entire range of .308 bullets. Don't assume accuracy will suffer as just about anyone here will attest to when they shoot 38's from a 357max ream job.

For me the whole point of owning a non m1 30carbine would be to have the ability to play with other projectiles. Ream that sucker out and don't look back!

[gcrank1]

FWIW, I concur