Dummy rounds

[Krh1326]

If you have a tough feeding , platform ( in my case I’m playing with an AR in 300 Blk ) and you are experimenting with different boolits, col , etc… can the empty case of your dummy round, contribute to what is going on, at nose of boolit, during feeding? If a nose heavy boolit is having an inconsistent feed at the ramps, would adding the ballast , of the equivalent of primer and your intended charge help?
I don’t like the idea of a live primer and powder during blatant feed and cycle, especially while working on a problematic combination. Would a spent primer installed, and maybe the equivalent powder weight in maybe some cured hot glue beads… make any kind of difference?

[44Blam]

So, comparatively, the primer/powder weight is pretty low compared to the boolit weight. Personally, I just have a boolit and a case and I seat/crimp as I would when loading them. If I booger up a boolit, I use a new one and put the boogered one back in the pot. No fuss.

[johnsonian09]

Spent primer and the same weight in grains of walnut shell/ corn grits/ abrasive media as your powder should do the trick.

Also there are 300blk specific mags that are slightly different from 223 mags. You may notice a difference.


Sent from my iPhone using Tapatalk

[Krh1326]

I get that the weight is nothing like the boolit, but just trying to think… could it be any help, in helping that nose go up, instead of dig down.

Yes different mag… to my eye, it looks like ribs in sides of mag are trimmed back further, than in 223/556 mag.

[johnsonian09]

What boolit are you trying to get cycling?


Sent from my iPhone using Tapatalk

[mehavey]

If you have feeding problems because powder weight isn't accounted for,
you still have feeding problems no matter what.

As asked above: what bullet, what nose design, what OAL?

[Krh1326]

What boolit are you trying to get cycling?


Sent from my iPhone using Tapatalk

https://www.mp-molds.com/product/mp-308-hunting-hp-gc-4-cav/

Same one in our group buys, that people were raving about. It’s on 3rd run.
I got my hands on one, from ePay.

Best feed I have so far, is in top of lube groove. Crimped in the lube groove , set in shoulder closest to nose.

303067

[johnsonian09]

That looks like a great Winchester or 30-06 bullet.

You’ll want to look over your barrels feed ramp extension to make sure it’s milled for 30cal.

Some brands still mill a standard m4 5.56 feed ramp on 300blk barrels. I’ve had this issue myself recently.

Round nose, hp, and flat points have more difficulty cycling.

I’ve had some success with round nose 30 carbine bullets similar to this but only 100grains. And hollow points with an s2 ogive but any blunter I get some problems.


Sent from my iPhone using Tapatalk

[Krh1326]

That looks like a great Winchester or 30-06 bullet.

You’ll want to look over your barrels feed ramp extension to make sure it’s milled for 30cal.

Some brands still mill a standard m4 5.56 feed ramp on a 300blk barrels. I’ve had this issue myself recently.

Round nose, hp, and flat points have more difficulty cycling.

I’ve had some success with round nose 30 carbine bullets similar to this but only 100grains. And hollow points with an s2 ogive but any blunter I get some problems.


Sent from my iPhone using Tapatalk

It’s a Ruger Model 556 rifle. I’ll have to investigate that, further, tomorrow.. had to walk away from it, for the night. It like it’s right on the line… some will feed then one won’t. Some will feed then one won’t.

[mehavey]

Before you do anything else, try a different/different brand magazine.
https://www.midwayusa.com/product/1018507080

[Krh1326]

Before you do anything else, try a different/different brand magazine.
https://www.midwayusa.com/product/1018507080

Pick my lottery numbers! That’s the mag we’re using. Pmag 300blk

The Lee 312-155 and 309-230 run right through it, nicely. I’m trying to give the kid a decent hunting round, and for the caliber… this boolit I’m working on, screamed try me, try me!

[mehavey]

Try anyone else's just plain old vanilla 5.56 mag then...
:happy dance: :roll: :mrgreen:

[barnetmill]

Before you do anything else, try a different/different brand magazine.
https://www.midwayusa.com/product/1018507080

I have found buffer wt makes a difference if you gun is over gassed. Slowing down the bolt speed with a heavier buffer gives some follower springs more time to lift of a round.

[johnsonian09]

With my short rn blackouts a 5.56 pmag is more reliable then the 300blk mag. GI mags have zero function. But my Coal is going to be shorter then yours by a fair amount. And that ar’s action is about as soft as it can get

I’ve been curious if a redesigned follower that increases the angle of the cartridge might help.


Sent from my iPhone using Tapatalk

[Soundguy]

If you have feeding problems because powder weight isn't accounted for,
you still have feeding problems no matter what.

As asked above: what bullet, what nose design, what OAL?

Agreed... If 15-20 grains cause the gun not to feed..work on the gun...

[Krh1326]

Good stuff… will go at it again, later, when I get home. I have Pmag gen 3s for my AR… Will give them a go.