getting enough power out of 10.5 and 11.5 barrels

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[ARCHIVED THREAD] - getting enough power out of 10.5 and 11.5 barrels

Posted: 12/30/2005 3:51:33 AM EDT

I was thinking in order to get the right amount of stopping power out of short barrels couldnt you use hand loads with pistol type propellant?

THis is what i was thinking. When using a conventional 223 or 556, which is designed for longer barrels (+-16"), The poweder is designed to burn itself up by the time the round reaches the end of the barrel. So in shorter barrels some of the loss of power can be attributed to the propellant burning once the bullet has left the barrel, which does nothing for the round.

So if a finer powder (faster burn rate) were to be used the propellant would burn up by the time the bullet reached the end of the 10.5 or 11.5 barrel, giving the round the necessary amount of power.

Thats my idea, now my questions:
Would this cause excess stress on the barrel? A dangerous amount?
Would this mess up the mechanism for chambering the next round?
Is it feasable to do this on a small scale?
And is my overall idea right????

PJ

Posted: 12/30/2005 3:59:19 AM EDT

[#1]

i wouldnt.

and theres a reloading forum in the general discussion board.

ibtl

Posted: 12/30/2005 5:25:50 AM EDT

[#2]

Ismlax006:
I agree and asked essentially a similar question in a different thread. When the 223 and AR15 were developped, the barrel length and powder matched for a full burn - perhaps an optimum burn. Where as longer barrels give some increase in speed, a too long barrel has the opposite effect.
My question was: if we went to 30 - 40gr bullets (and changed the load), wouldn't we be able to have a better performing 101/2 - 11 1/2" barrel system with also higher bullet speed as opposed to 55-62gr.

Posted: 12/30/2005 5:53:37 AM EDT

[#3]

There are alredy probs with the shorter barrel systems being too hard on the gas systems, bolts, etc (that's why we ahve H, H2, and H3 buffers in the shorter weapons). If you increased the burn you would also increase pressure. Not only would the chamber's ability to withstand the increased pressure be questionable, but the reliablity issues would be increased as well.
The shorter barrels are generally used by certain people in certain situations where the "power" limitations aren't that big an issue. The guys who stopped the attempt on Kharzai a few years ago were using the Crane 10.5" system. Furthermore, that's what the Mk262 is for.

Posted: 1/2/2006 5:22:26 AM EDT

[#4]

The AR platform was not designed to accomodate the SBR concept. It is a sub-optimal implementation of the weapon platform and the ammunition. It's a comprimise that some are willing to make, however.

You simply won't get reliable fragmentation from the 10.5" & 11.5" barrels. To my way of thinking, this makes the typical mil-spec ammo a poor choice for these guns. I would use a round that relies on an expanding bullet to achieve it's best terminal performance.

Playing around with non-conventional reloading techniques is dangerous and, usaully, ill-advised.

Posted: 1/2/2006 5:32:07 AM EDT

[#5]

Quoted:
You simply won't get reliable fragmentation from the 10.5" & 11.5" barrels with M193 and M855 USGI ammunition.

results vary with other loadings

Posted: 1/3/2006 5:30:51 AM EDT

[#6]

I hate it when I show my ignorance, but that's how I learn. I was under the impression that M193 and M855 (and their tracer eqivalents) were the only current mil-spec ammo. I know some forces use other ammo, but I didn't think that made the ammo mil-spec. IOW, if the military specifies all the characteristics of a round - that's what I thought made it mil-spec. If they simply use, on a limited basis, rounds designed and specified by another entity or company - I thought wasn't the same.

But, I'm no expert and simply rely on what I read on sites like this and ammo-oracle. But I'd like to learn more. What is the mil-spec number for these other rounds and what are they? Also, what is their reliable fragmentation range using the 10.5" and 11.5" platforms?

Thanks.

Posted: 1/3/2006 6:55:19 AM EDT

[#7]

Quoted:
I was thinking in order to get the right amount of stopping power out of short barrels couldnt you use hand loads with pistol type propellant?

PJ

You could, however, you could also end up eating through a straw after a trauma team got done with you.

Posted: 1/3/2006 8:26:38 AM EDT

[#8]

Quoted:
I hate it when I show my ignorance, but that's how I learn. I was under the impression that M193 and M855 (and their tracer eqivalents) were the only current mil-spec ammo. I know some forces use other ammo, but I didn't think that made the ammo mil-spec. IOW, if the military specifies all the characteristics of a round - that's what I thought made it mil-spec. If they simply use, on a limited basis, rounds designed and specified by another entity or company - I thought wasn't the same.

But, I'm no expert and simply rely on what I read on sites like this and ammo-oracle. But I'd like to learn more. What is the mil-spec number for these other rounds and what are they? Also, what is their reliable fragmentation range using the 10.5" and 11.5" platforms?

Thanks.

I think you are confusing type classification (the "M-" number or "Mk-" number) with mil-spec.
The Mk262 Mod0/1 are by definition mil-spec. Just because it is not general issue to the entirety of the end-users of the M4/16 and similar platforms doesn't make it not mil-spec. The M855/856 ammo is best thought of as general issue. Mil-spec just means it meets the data specs that have been set out by some part of the .mil for a specific use or platform, however small. You have Craftsman tools that would be mil-spec in the small arms rep shop, but those would be completely different form the special alloy tools that are used elsewhere. They are both mil-spec, just different specs.

Posted: 1/3/2006 12:29:10 PM EDT

[#9]

Quoted:
The AR platform was not designed to accomodate the SBR concept. It is a sub-optimal implementation of the weapon platform and the ammunition. It's a comprimise that some are willing to make, however.

You simply won't get reliable fragmentation from the 10.5" & 11.5" barrels. To my way of thinking, this makes the typical mil-spec ammo a poor choice for these guns. I would use a round that relies on an expanding bullet to achieve it's best terminal performance.

Playing around with non-conventional reloading techniques is dangerous and, usaully, ill-advised.

An 11.5" barrel with MK262 or 5.56 75 grain TAP will reliably fragment beyond 100 yards. This type of ammo is far superior in its terminal ballistics to soft point ammo. This is more than adequate performance for 99.9% of all civilian and LE purposes. As was stated previously MK 262 is a mil-spec ammo. M193 is not a current milspec ammo and has not been for many years.

+1 on not trying to use pistol powder in your rifle. You will probably blow up your gun.

Posted: 1/3/2006 1:24:50 PM EDT

[#10]

Quoted:
Quoted:
The AR platform was not designed to accomodate the SBR concept. It is a sub-optimal implementation of the weapon platform and the ammunition. It's a comprimise that some are willing to make, however.

You simply won't get reliable fragmentation from the 10.5" & 11.5" barrels. To my way of thinking, this makes the typical mil-spec ammo a poor choice for these guns. I would use a round that relies on an expanding bullet to achieve it's best terminal performance.

Playing around with non-conventional reloading techniques is dangerous and, usaully, ill-advised.

An 11.5" barrel with MK262 or 5.56 75 grain TAP will reliably fragment beyond 100 yards. This type of ammo is far superior in its terminal ballistics to soft point ammo. This is more than adequate performance for 99.9% of all civilian and LE purposes. As was stated previously MK 262 is a mil-spec ammo. M193 is not a current milspec ammo and has not been for many years.

+1 on not trying to use pistol powder in your rifle. You will probably blow up your gun.

But the pix would be better than the underwater bumpfire thread!!!

Posted: 1/3/2006 1:34:04 PM EDT

[#11]

Quoted:
But the pix would be better than the underwater bumpfire thread!!

But we would have to wait for either the NOK to post them or for him to learn how to type with his toes.

Posted: 1/3/2006 1:38:13 PM EDT

[#12]

Ahh no worries, my home loads come from my dad. I was just wondering if it would work in theroy

Posted: 1/3/2006 2:15:04 PM EDT

[#13]

You would want (need) to reduce the case capacity for teh smaller charge, this has all been before and did work well really - What you want to read up on is the MARS rifle.

Posted: 1/3/2006 2:23:01 PM EDT

[#14]

Shot placement is more important to me than using some strange hand loads or $2 a round ammo.

Posted: 1/3/2006 3:18:58 PM EDT

[#15]

+1

Posted: 1/3/2006 3:30:56 PM EDT

[#16]

It would be a cool way to rid the world of vulcan and hesse, using remote firing, of course!

Posted: 1/3/2006 3:33:44 PM EDT

[#17]

Quoted:
Ahh no worries, my home loads come from my dad. I was just wondering if it would work in theroy

When you ask him to do this, if he's any kind of handloader, he may just biff your noggin'...

Posted: 1/3/2006 3:41:47 PM EDT

[#18]

Quoted:
But we would have to wait for either the NOK to post them or for him to learn how to type with his toes.

I happen to have some handy

many more kBs

Posted: 1/3/2006 4:07:29 PM EDT

[#19]

Damn cast receivers and bbls...

Posted: 1/3/2006 5:14:00 PM EDT

[#20]

yep those cast barrels are the worst

Posted: 1/4/2006 3:30:15 AM EDT

[#21]

Im not going to do this. It was just an idea, somethign i wanted to see if it was feasable. And by saying my dad handloads was my way of saying there is no way in hell it would ever happen. Sorry for the confusion

And Spectre1, I am very accustomed to dope slaps.

THanks
PJ