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  #1  
Old 02-27-2009, 01:28 PM
conchmariner conchmariner is offline
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M193 Vs M855 For AR15




Any thoughts? M193 seems more popular ie harder to get right now. Also what does the X designation mean ie XM193, XM855?
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  #2  
Old 02-27-2009, 02:16 PM
mr2guru mr2guru is offline
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193 is just ball. m855 is the green tip penetrator (SS109).
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  #3  
Old 02-27-2009, 02:56 PM
Brian48 Brian48 is offline
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I believe the M193 is also a slightly lighter bullet at 55gr versus 62gr for the SS109. This is of issue if your particular carbine has a slower twist. If memory serves, the original twist rate was 1:12 with the M16A1, but this was later change to 1:7 for the M61A2 to accomodate the really heavy tracer round (70gr?).

Anyway, any rifle barrel with a twist of 1:10 or faster should be fine with the SS109. My old mini-14 had a 1:10.
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  #4  
Old 02-27-2009, 07:08 PM
Amos Iron Wolf Amos Iron Wolf is offline
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While you should always study a variety of sources, here are some diagrams at:
http://www.firearmstactical.com/pagea18.htm

And here is the text from: http://www.firearmstactical.com/briefs13.htm

Wounding Effects of the U.S. Military M193 (M16A1) and M855 (M16A2) Bullet Cartridges

Exaggerated descriptions of the wounding effects of the M16 rifle bullet flourish as great works of urban lore. One fable describes a bullet that tumbles end-over-end in flight as soon as it exits the muzzle of the rifle. Another legend provides a dramatic account of an unstable, super-high velocity bullet that tumbles and chews its way through flesh like a buzz saw. Although there appears to be a tinge of half-truth behind these entertaining and awe-inspiring mythical tales, these stories do not represent an accurate description of the wounding characteristics of the M16 bullet.

When the M16 cartridge is fired and the bullet is propelled down the bore, the boreís rifling imparts a gyroscopic spin to the bullet. This gyroscopic rotation is needed to maintain point forward stabilization of the bullet as it flies through the air. This method of bullet stabilization is identical to the rotational spin applied to a football when thrown by a quarterback (American football).

The Earthís gaseous atmosphere is approximately 400 times less dense than the body's soft tissues. When the M16 bullet strikes and plows into the body, the rotational spin that stabilized its flight through the air is insufficient to maintain its stability as it flies through dense tissue. The bullet typically penetrates point forward for approximately 4-5 inches before it begins to seek a state of stability in the body.

The bulletís pointed shape makes it heavier at its base than its nose, producing a center of gravity that is located aft of its longitudinal centerline. When the bullet hits the body and penetrates, the bullet attempts to rotate 180 degrees around its center of gravity to achieve a base forward orientation. This backwards orientation is the bulletís stable position in tissue because it places the center of gravity forward.

As the bullet yaws through 90 degrees and is traveling sideways through flesh, the stress of tissue resistance to bullet passage can overpower the physical integrity of the bullet. The bullet has a groove around its midsection called a cannelure. The purpose of the cannelure is to permit the mouth of the cartridge case to be crimped tightly against the bullet shank to hold it firmly to the case. The cannelure weakens the structural integrity of the bullet's copper jacket.

At distances of 100 yards and under, when the bullet hits the body and yaws through 90 degrees, the stresses on the bullet cause the leading edge to flatten, extruding lead core out the open base, just before it breaks apart at the cannelure. The portion of the bullet forward of the cannelure, the nose, usually remains in one piece and retains about 60 percent of the bullet's original weight. The portion of the bullet aft of the cannelure, the base, violently disintegrates into multiple lead core and copper jacket fragments, which penetrate up to 3-inches radially outward from the wound track. The fragments perforate and weaken the surrounding tissues allowing the subsequent temporary cavity to forcibly stretch and rip open the multiple small wound tracks produced by the fragments. The resulting wound is similar to one produced by a commercial expanding bullet used for varmint hunting, however the maximum tissue damage produced by the military bullet is located at a greater penetration depth.

(The increased wounding effects produced by bullet fragmentation were not well understood until the mid-1980ís. Therefore the wounding effects of the original M16 rifle bullet were not an intentional U.S. military design characteristic.)

At distances between 100-200 yards the bullet commonly breaks in half at the cannelure forming two large penetrating fragments, the nose and base.

At distances beyond 200 yards the bullet usually remains intact due to velocity decay. It simply yaws 180 degrees to penetrate backwards through the body.

Both the M193 and M855 bullets demonstrate similar terminal performance as described above, when fired from rifles fitted with a 20-inch or longer barrel.

Shooting the M193 or M855 from a rifle with a barrel length less than 14.5-inches produces insufficient muzzle velocity to achieve the terminal performance described above. A rifle fitted with a 14.5-inch barrel is adequate for close-quarters battle. For engagements anticipated at greater than room distance but less than 100 yards, a rifle fitted with a 16.5-inch barrel should be employed to ensure sufficient velocity.

The older 55-grain M193 (M16A1) cartridge is not sensitive to rifling twist rate and can be fired in rifles with 1:12, 1:9 and 1:7 rates of twist. However, the newer M855 (M16A2) cartridge is best used with a rifling twist rate of 1:7 or 1:9. When the M855 is fired in a rifle with a slower rate of twist the longer 62-grain bullet can yaw up to 70 degrees in free trajectory through the air, substantially degrading accuracy.

The wound ballistics of the U.S. military Olin M193/Winchester 55 grain FMJ (X223R1 or Q3131) and green tip U.S. military Olin M855/Winchester 62 grain FMJ (RA556M855) cartridges makes them an adequate choice for use against violent criminal offenders.

Additional testing has indicated that errant bullets (military FMJ and commercial .223 Remington JSP/JHP) which do not hit an attacker appear to penetrate fewer walls and other common building materials than stray handgun bullets.
End of quoted text.

Things to keep in mind are (IMO):

Bullet construction matters. Not all Full Metal Jacketed bullets are the same. The cannelured NATO bullets (M193 and M855) and similarly constructed, are the ones that break. Wolf has a bi-metal jacketed bullet. The new brass-cased Monarch FMJ does not appear to have a cannelure.

Velocity is critical. Once either the M193 or the M855 bullet drops below that 2700 something speed both bullets pretty much just act like any other full metal jacketed bullet. Because of this barrel length plays a big part in distance over which you can expect the more nasty effect. To another degree, bullet weight will have some affect in as much as it affects velocity loss over a given range.

There are always other factors and other factions to examine. People do have different opinions (some based on actual research) and more importantly, different experiences with the same situations.

Everything in this game is going to be a compromise. You can't have a round that pops bad guys behind walls and have the same round magically decide to not penetrate walls when good guys or innocents are on the other side. You can't have a shorty barrel and expect to get the above mentioned wound ballistics over the same range that you will with a 24" barreled rifle. Barrel length affects velocity, velocity affects bullet action, and a bullet that starts out slower at the muzzle is going to drop below the magic speed mark at a closer distance than one starting out faster.

For the above reasons I currently pick up (when I can find it) some Wolf/Monarch when I can to burn up in practice and I pick-up either Monarch Soft Points and/or Federal XM193F to stockpile for social work for Samantha my 16" barreled Saiga. "For engagements anticipated at greater than room distance but less than 100 yards, a rifle fitted with a 16.5-inch barrel should be employed to ensure sufficient velocity." That pretty much fits my battle plan. For poking holes in barriers at close range I have shotguns with buckshot and slugs.

Hope that helps some. All take note. This was not a .223 vs 7.62x39 vs .308 thing. Just presenting the info. Each person has to study and select what they feel comfortable with in their SHTF scenarios, dreams, and nightmares.
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  #5  
Old 02-27-2009, 08:21 PM
Damascus Damascus is offline
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The "X" is for eXperimental, meaning that the military hasn't deemed it for normal issue.. like the new sniper rifle, the M110, was formerly the XM110. The XM193 is a hotter version of the M193, still uses the 55gr. FMJ ball.
As far as which one is better, NEITHER bullet is good for combat use, but if I were forced to choose, I would choose the M855. The longer, heavier 62gr. bullet is more accurate in most rifles, and hits the target with much more authority - and penetrates quite a bit better than M193.
The M193 is extremely bad to totally fragment on impact, which is bad because although it leaves a nasty wound, it doesn't penetrate deep enough to damage any vitals. The M855 also fragments, but it usually gets into the vitals if the target is unarmored and under 200 yards. The steel "penetrator" cores in those don't do much IMO.
If you want some good combat rounds, look at the 60gr. V-Max for CQB, and I've been hearing GREAT things about the new Speer 64gr. Gold Dots. For a great combat round thats also super accurate, try something that's loaded with either 69gr. Sierra Matchkings, 75gr. Hornady Match BTHP (loaded in Hornady's TAP, also called 75gr. OTM for Open Tip Match - just a new label for BTHPs), and the 77gr. Sierra Matchking for the best terminal ballistics (if you have a 1/7" or 1/8" twist barrel - all the others, 64, 69, and 75 can be shot with 1/7" and most 1/9" barrels).
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  #6  
Old 02-27-2009, 08:45 PM
MyGlockWorks MyGlockWorks is offline
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No, the X does not mean experimental. The 5.56 is hotter than .223 by it's nature. The X just means it fail some QC inspection or was part the the M193 military contract overrun that the military canceled.

The M856 tracer is not that much heavier(about 64grs) than the M855, just a lot longer.

The M855 only penetrates better than the M193 beyond 200m. Inside that range, the M193 will out penetrate the M855. Why? Velocity.

The M193 has a better rep for fragmentation, however with the shorter barrels, that fragmentation velocity threshold will limit your range. The fragmentation is never a sure thing either way. The threshold with the M855 out of a 14.5" barreled weapon is about 45m if I remember correctly.
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  #7  
Old 02-27-2009, 09:32 PM
Amos Iron Wolf Amos Iron Wolf is offline
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Quote:
Originally Posted by Damascus View Post
The M193 is extremely bad to totally fragment on impact, which is bad because although it leaves a nasty wound, it doesn't penetrate deep enough to damage any vitals...

...If you want some good combat rounds, look at the 60gr. V-Max for CQB...
This is contradictory and completely illogical. It also is absurd. If you think think that the M193, a full metal jacketed bullet, fragments too easily to reach vitals, and I would refer you to the illustration where tumbling doesn't even start until a depth of around 5 or 6 inches, where fragmentation starts, then what do you think a V-Max bullet is going to do? Hornady V-Max bullets are varmint bullets, hence the V, designed to fragment explosively on contact with very little penetration.

The FAQ over on AR15.com http://www.ar15.com/content/page.html?id=185 has some good info. Note under Loads to Avoid:

Loads To Avoid

Anything loaded with a varmint bullet; all varmint bullets in this caliber will underpenetrate from all guns. This means NO VMax bullets (including TAP loads),(emphasis added) NO Nosler/Combined Technologies "Ballistic Tip" bullets, and so on. Varmint bullets were designed for animals no larger than 60 lbs., with the lighter bullets being designed for even smaller animals. They are NOT combat bullets, regardless of marketing to the contrary.


Even the Hornady pdf pamphlet states: The copper jacket is designed to work
with the tip to deliver incredible accuracy
at long range, and it assists the V-MAX’s
dramatic expansion. The copper jacket
provides the necessary bearing surface
for maximum in-fl ight stability. Inside
the barrel, the jacket is built to withstand
the faster twist rates of many of today’s
advanced varmint rifl es. It all means the
bullet will hold together until impact.


Also, as noted by MyGlockWorks, the X is not for experimental. His explanation is the correct one. Yes, X has been used by the military in that manner. My M16A1 at Fort Bragg was stamped XM15E1 and had a 6 digit serial number (this was in 1988, it was obviously a refurb and reissue). The M9 was originally the XM9. However, that ain't the case in this case. As MyGlockWorks states, either seconds or contract overruns.
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Last edited by Amos Iron Wolf; 02-27-2009 at 09:34 PM.
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  #8  
Old 02-27-2009, 10:12 PM
MyGlockWorks MyGlockWorks is offline
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I also have to say the 60 gr VMAX is a poor choice. I have heard poor performance from the 60 gr load in actual shootings. Poor as in about 4" of penetration on badguys.

No, I can't reference you to the documentation, you can take it or leave it.
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  #9  
Old 02-28-2009, 11:04 AM
DR505 DR505 is offline
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Our duty/issue round for our 16" barreled (1:7 or 1:9 twist) 5.56mm chambered M-4s is the Winchester LE loading of the 62 grain Nosler Partition. We get it in .223 Rem flavor, but use the 855 as our practice round (much cheaper).
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  #10  
Old 02-28-2009, 01:30 PM
conchmariner conchmariner is offline
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Thanks for that detailed, interesting and useful explanation AmosIronWolf. The barrel twist on my AR is 1:9, so I guess I can use either round from everything I've read. Main purpose is for SHTF HD, a scenario I hope I never see.
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Old 02-28-2009, 06:54 PM
Amos Iron Wolf Amos Iron Wolf is offline
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Quote:
Originally Posted by conchmariner View Post
Thanks for that detailed, interesting and useful explanation AmosIronWolf. The barrel twist on my AR is 1:9, so I guess I can use either round from everything I've read. Main purpose is for SHTF HD, a scenario I hope I never see.
Por Nada. I actually was writing some stuff then realized it had already been written before by people with some serious time invested in this stuff. Besides, it sounds better coming from the source.

Yep, with the 1:9 twist you should be good to go on both rounds. Nice thing using those in an AR (in 5.56 chamber, not the .223 varmint/target rifle chambers.) is that the M16/AR15 platform and those rounds are literally made for each other. Those should be your most trouble-free rounds. Sighted for one you shouldn't be off by much, at least according to the published data (FMs and the like) over the first few hundred meters for anti-personnel purposes.

While some of the heavier, tactical and game type loads have a bit more going for them in the CQB/Urban Battle scenario, those loads cost enough more to really add up over hundreds of rounds. You can build more stock and actually be able to actually practice with the 193/885 stuff without going completely broke.

Good input from DR505 & MyGlockWorks to0.

What I would love to hear/see is some unbiased and honest feedback from guys who used these round in the sandbox in real battles with real combatants. I would especially love to hear direct, real-world, comparisons between the 5.56 and the 7.62x39 in urban and CQB environments.
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Old 08-29-2009, 12:49 AM
SSG_Scott SSG_Scott is offline
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Terminal Performance related to TWIST

My opinion is based primarily on information obtained from the following article:

“In Praise of the M16 Rifle” By Chuck Taylor
From the June/July 2009 issue of SPECIAL WEAPONS for Military and Police Magazine.

Many of the facts stated in this post are direct or slightly modified quotes from the article written by Mr. Taylor.
For information regarding Chuck Taylor’s experience and knowledge, please follow the link http://www.chucktaylorasaa.com/aboutchuck.html

When Eugene Stoner originally designed the M16, it had a 1/14 Twist and fired a 55 grain bullet. The 1/14 twist BARELY stabilized the round in flight causing it to destabilize and tumble upon impact. This caused “Fantastic” wounds and excellent stopping power. However during testing, the Air Force discovered that the 1/14 twist did not stabilize bullets well enough to meet US Military accuracy specifications in sub zero climates. “Someone” at Springfield Armory (then a US Government installation) authorized a change in the twist from 1/14 to 1/12 for ALL M16’s. The INCREASED stabilization caused a 40 percent reduction in stopping power. In 1983 the Army (responsible for small arms development for all the US armed forces) COMPOUNDED the problem by adopting a 1/7 twist for the new M16A2. This was so the M16A2 and the evolving M249 Squad Automatic Weapon could SHARE the heavier and longer SS109 ammunition. The 1/7 Twist further INCREASED bullet stabilization...and DECREASED stopping power by perhaps another 20 percent.

To me, this information indicates that the 62 Grain M885 Ball ammunition fired through a 1/7 Twist conceivably has 60 percent less stopping power then it’s 55 grain predecessor being fired through a 1/14 Twist. I don’t have to point out that lack of stopping power is the primary complaint regarding the M4 and M16A2 in combat. Keeping all this in mind, it seems reasonable that the further you step away from Eugene Stoners original 1/14 twist, the more you decrease the stopping power of the bullets you are firing.

BUSHMASTER states (http://www.bushmaster.com/faqs/afmvi...aspx?faqid=172) that the 1/9 twist will handle 40 to 75 Grain ammunition with ľ to Ĺ inch groups. I have read on various forums that if you have to relegate to shooting lower grain bullets, like 40 grain or less through a 1/7 twist, the bullet can spin apart before it leaves the barrel. If the weapon is to be used in a COMWEC (Complete Meltdown of Western Civilization) situation, or some other SHTF scenario, the 1/9 twist will accurately and safely fire the wider range of bullet weights that a person might “acquire” along the path of survival, as well as provide improved Terminal Performance over the 1/7 Twist.

As a military veteran, I have seen the M16 evolve from the M16A1 all the way through to the A4 and M4 series of rifle. This by no means makes me an expert. However, history has taught us that the U.S. Army hasn’t always made sound decisions in regards to things of this nature. Ignoring Eugene Stoners recommendation for the M16 to have chrome lined chambers and barrels in the early days of the M16 is a testament to that. Just because the Army opted for the 1/7 Twist with the adoption of the M16A2 doesn’t necessarily mean it was the RIGHT decision. The army would never make a mistake....right? Articles I have read regarding the decrease in Terminal Performance from the original designs of the M16 seem to be directly linked to the change in twist rate. It seems that the Army chose ammunition compatibility with the M249 SAW over Terminal Performance (Stopping Power). There may well be other factors, but they are unknown to me.

Last edited by SSG_Scott; 08-29-2009 at 12:55 AM.
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  #13  
Old 08-29-2009, 01:20 AM
N/Apower N/Apower is offline
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Quote:
Originally Posted by MyGlockWorks View Post
No, the X does not mean experimental. The 5.56 is hotter than .223 by it's nature. The X just means it fail some QC inspection or was part the the M193 military contract overrun that the military canceled.

The M856 tracer is not that much heavier(about 64grs) than the M855, just a lot longer.

The M855 only penetrates better than the M193 beyond 200m. Inside that range, the M193 will out penetrate the M855. Why? Velocity.

The M193 has a better rep for fragmentation, however with the shorter barrels, that fragmentation velocity threshold will limit your range. The fragmentation is never a sure thing either way. The threshold with the M855 out of a 14.5" barreled weapon is about 45m if I remember correctly.
Tested by me on 3/8" steel plate, M855 was superior from 25M and back. I did not fire at it closer than 25M. The M193 caused spalling, and pushed a chunk of metal into the 2x4 behind my plate, denting the 2x4 badly. The M855 penetrated the plate and the steel core in the tip continued to through-through the 2x4. The Q3131 I had did this out to 120-130m with SOME shots, it was VERY inconsistant and chronographed anywhere from around 3180 to 3375 IIRC (it also grouped into about 3.5MOA at 100m). I think it was the hotter loads still knocking a hole in the plate out to the longer range. The M855 reliably punched it like butter and through the 2x4 as well out to the maximum distance I had at the time, @150m.

On pine-boards stacked, again the M855 out-penetrated the M193.

The PPU M855 I have ran 1.8MOA at 200 yards from a CAR A3 Elite w/10X leupold on it. The Federal M193 I have ran 2.0 MOA at this range. 10-shot groups. No fliers.

1/9 twist provides a G-Stab factor of @ 1.3 with the M855 projectile. Very optimal.

For plinking, buy what is cheap, for self-defence, buy 5.56 75gr Tap T2 in the red-boxes. For defence where cars are involved, buy LE223T3 from federal or DPX from Corbon.

Last edited by N/Apower; 08-29-2009 at 01:25 AM.
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Old 08-29-2009, 01:18 PM
SSG_Scott SSG_Scott is offline
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Ballistics Gel

I have an ongoing debate with my brother in law as to whether the 1:7 twist is superior to the 1:9 twist. I am in favor of the 1:9 while he favors the 1:7. My reasons for supporting the 1:9 are stated in my previous post. We are discussing making up some home made ballistics gel to conduct our own tests. We both have AR's with 16.5 inch barrels. His has a 1:7 twist while mine has 1:9. We intend to put M193 and M885 through both weapons...probably from CQB range out to 100+ meters. Does anyone know the best recipe for home made ballistics gel, or conducted a similar test? I'd love to hear the results.
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Old 08-29-2009, 02:27 PM
N/Apower N/Apower is offline
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Quote:
Originally Posted by SSG_Scott View Post
I have an ongoing debate with my brother in law as to whether the 1:7 twist is superior to the 1:9 twist. I am in favor of the 1:9 while he favors the 1:7. My reasons for supporting the 1:9 are stated in my previous post. We are discussing making up some home made ballistics gel to conduct our own tests. We both have AR's with 16.5 inch barrels. His has a 1:7 twist while mine has 1:9. We intend to put M193 and M885 through both weapons...probably from CQB range out to 100+ meters. Does anyone know the best recipe for home made ballistics gel, or conducted a similar test? I'd love to hear the results.
Home-made gel=fail. Gel must be calibrated, shot within a narrow temperature range, etc. Only professionally prepaired gel will give professional results.

Your best bet is to use news-paper that has been soaked for 24 hours.

1:7 vs. 1:9 won't matter much with the rounds you are using. Results will probably be identical. However, with a 1:7 twist, he will be able to utilize the 75gr Tap T2. This will blow your mind with what it does to the soaked newspaper compared to M193/M855. Some 1:9 barrels will stabalize it, some won't. Depends on if it's a 1:8.5 or a 1:9.5 pretty much. Variances do occur.
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Old 08-29-2009, 03:40 PM
SSG_Scott SSG_Scott is offline
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Twist and Gel

Quote:
Originally Posted by N/Apower View Post
Home-made gel=fail. Gel must be calibrated, shot within a narrow temperature range, etc. Only professionally prepaired gel will give professional results.

Your best bet is to use news-paper that has been soaked for 24 hours.

1:7 vs. 1:9 won't matter much with the rounds you are using. Results will probably be identical. However, with a 1:7 twist, he will be able to utilize the 75gr Tap T2. This will blow your mind with what it does to the soaked newspaper compared to M193/M855. Some 1:9 barrels will stabalize it, some won't. Depends on if it's a 1:8.5 or a 1:9.5 pretty much. Variances do occur.
N/Apower: Cool. Thanks. Not sure about the twist. I just know it is an ER Shaw barrel with a 1:9 twist. Bushmaster says their 1:9 barrels have been reported to shoot 75 gr with 1/4 to 1/2 inch groups. I'll have to buy a box of TAP T2 and try it out. I really never intended to break the 62 grain barrier. I pretty much stick to M193 and M885. My rifle is my COMWEC/SHTF weapon, and I figured if it ever comes down to recovering ammo from "third parties", the majority of it would be 55 or 62 grain. I have found that trajectory wise the M193 and M885 are pretty much the same from about 25 to 100 meters.

Do you have any specifics on the newspaper? Sounds a lot cheaper than making Gel anyway...Also....what do you know about the newer PTR-91 from JLD? I am thinking about picking one up.
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Old 03-09-2012, 05:01 PM
oldvet53 oldvet53 is offline
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Quote:
Originally Posted by MyGlockWorks View Post
No, the X does not mean experimental. The 5.56 is hotter than .223 by it's nature. The X just means it fail some QC inspection or was part the the M193 military contract overrun that the military canceled.

The M856 tracer is not that much heavier(about 64grs) than the M855, just a lot longer.

The M855 only penetrates better than the M193 beyond 200m. Inside that range, the M193 will out penetrate the M855. Why? Velocity.

The M193 has a better rep for fragmentation, however with the shorter barrels, that fragmentation velocity threshold will limit your range. The fragmentation is never a sure thing either way. The threshold with the M855 out of a 14.5" barreled weapon is about 45m if I remember correctly.
When the M193 was first fielded, the powers that be at the International Conventions deemed the bullet to cause excessively serious wounds to be inhumane and it fell out of favor. the M855 was originally designed to be for use in the S.A.W. and was adopted as the standard round for the military. The M193 from a 16"bbl with a 1:14 or 1:7 twist rate is required to stabilize the bullet. The M193 is the best round for a 16" bbl. out to 150 meters as it retains 2700fps which is required to cause the bullet to yaw and self destruct causing the better wounding capability. The M855 is best out to 90-95 meters from the short bbl. carbines and it requires a 1:7- 1:9 twist to stabilize not because of bullet weight but because of bullet length.
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Last edited by oldvet53; 03-09-2012 at 05:09 PM. Reason: correction
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  #18  
Old 03-09-2012, 09:29 PM
moxie moxie is offline
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Quote:
Originally Posted by SSG_Scott View Post
N/Apower: Cool. Thanks. Not sure about the twist. I just know it is an ER Shaw barrel with a 1:9 twist. Bushmaster says their 1:9 barrels have been reported to shoot 75 gr with 1/4 to 1/2 inch groups. I'll have to buy a box of TAP T2 and try it out. I really never intended to break the 62 grain barrier. I pretty much stick to M193 and M885. My rifle is my COMWEC/SHTF weapon, and I figured if it ever comes down to recovering ammo from "third parties", the majority of it would be 55 or 62 grain. I have found that trajectory wise the M193 and M885 are pretty much the same from about 25 to 100 meters.

Do you have any specifics on the newspaper? Sounds a lot cheaper than making Gel anyway...Also....what do you know about the newer PTR-91 from JLD? I am thinking about picking one up.
ssg scott, Check youtube for terrific ballistic gel work done by tnoutdoors:
http://www.youtube.com/user/tnoutdoo...e=results_main
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Old 03-10-2012, 09:21 PM
mark2734 mark2734 is offline
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The reason the US went with the SS109 steel tip round was because of NATO requirements.

Prior to the SS109 bullet the 5.56 round had largely been a US thing. In the mid 80s NATO was looking to adopt the round but want it to have similar pentatration against WARSAW Pact body armor and helmets as the 7.62 round.

The 55 gr 5.56 bullet could not meet the pentatration requirements. At the same time the Marine Corps was looking to improve the long range accuracy of the service rifle, all of which resulted in the M16A2 service rifle and M855 round.
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