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 What do M vs. XM and all those suffixes mean?
dontalo  [Member]
9/30/2011 11:34:01 AM EDT
Comparing ammo prices is confusing for me. On Palmetto alone, there are 8 different types of 5.56 at 8 different price points.
M193, XM193BL, XM193J, XM193BK, XM193CBP, M855, XM855, XM855LC, and I probably overlooked a couple.
It looks like 193's weight 55gr and 855's weigh 62gr. The rest is a mystery to me.

Is there a FAQ page or reference that can help me understand what all the NATO designations mean?

I just shoot for fun and I am not competitive. I have always just purchased the cheapest I could find, trying to keep it below $0.30/round after shipping. Should I be putting more thought into this?

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firepyro515  [Member]
9/30/2011 12:04:34 PM EDT
Federal Arms XM193

Most of the variation that i have seen within the XM193 will relate to how they are packaged. 20rnd boxes, 200rnd boxes (split into 20), Stripper clips

XM193 is 55gr because it uses a lead core vs 855 and SS109 that use steel cores which bump them up to 62gr

If you are just plinking, i would use the XM193
PFC  [Member]
9/30/2011 12:09:39 PM EDT
M193/M855 should designate mil-spec ammo.
XM193/XM855 are Federal’s trade names for ammo produced at the US government Lake City ammo plant. According to Federal this ammo is composed of over runs and lots that were not acceptable to the government for any number of reasons, but are safe to shoot.
The extra letter(s) on the end designate packaging. Federal claims it is all the same ammo, but the statistics in the ammo FAQ dispute this.
dontalo  [Member]
10/5/2011 7:33:35 AM EDT
Thank you. Great answers. Good link.

As always, good answers beget deeper questions.
Are M193/M855 standards? I ask because I see other brands who I am pretty sure are not military suppliers (Prvi, PMC) using M193 and M855 designations. I also see brands (Centurion) that use the M193 designation for .223 ammo. Is there an implied quality standard here? Are these worth the couple of bucks savings, or should I just stick with Federal/AmEagle?

Thanks again.
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Saddlerocker  [Member]
10/5/2011 8:43:56 AM EDT
Privi is Serbian and M193/M855 their surplus ammo
PMC X-Tac M193/M855 is South Korean Surplus

All the letters after XM193 or XM855 only designate different packaging that Federal uses.
Some comes loose packed, some on stripper clips, some in 20rnd boxes ect....

There is Debate if any ammo XM193/XM855 that Federal sells, is quality control rejected ammo, because apparently they are not allowed to sell surplus ammo to the Civilian market.
People say thats what the "X" prefix means. Other Manufacturers like IMI, Privi, PMC, dont use any prefix
Weather thats just some technicality, or literally means nothing, I dont think any of us know for sure.
There have been conflicting reports about what people heard from Federal, so I dont know. What I do know is that it meets the Commercial SAMMI specs and that means its gtg.

So some people think that IMI (Israeli) PMC X-Tac (South Korean) Privi (Serbian) is better ammo, because they are allowed to sell surplus ammo to our market.

I dont know what is true, but I know that The Federal stuff seems as good as any other and I would never hesitate to buy it, but I buy whatever is cheapest. (currently stocked up on IMI and PMC X-Tac)
mrbullets  [Member]
10/5/2011 12:50:21 PM EDT
" IMI (Israeli) PMC X-Tac (South Korean) Privi (Serbian) is better ammo, because they are allowed to sell surplus ammo to our market. "

Actually all of the aforementioned ammunition presently available is new commercial production, not surplus. Supposedly manufactured to milspec if designated M193, M855, etc.
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