M118 Match vs Mexican Match

I've always been curious to see if the old trick of replacing a military bullet with match grade one was worth all the effort. And I wanted to see for myself if breaking the neck sealant on military ammo really improves accuracy. So I did a small test - and I learned a few things.

I still have a few rounds of M118 Match 68 (7.62X51MM NATO) and that's what I used for my test. Test Rifle was my Savage 10FLP (straight from the factory except for the McMillan HTG stock). This was not an exhaustive, meticulous test by any definition - just for fun.

When I started pulling the original Lake City bullets I ran into a problem. I had deep seated twenty rounds last year and never gotten around to shooting them. I was using ten of those for my Mexican Match. When I started pulling the bullets I noticed a few were really tough to pull and it looked like the sealant had seized up again. These rounds needed a second seating to break the seal again. The other ten were probably the same way and I'm pretty sure it had an effect on the results. I didn't want to seat the bullets any deeper so I left them alone. All groups fired at 100 yards.

[img width=600 height=348]http://i218.photobucket.com/albums/cc265/pbcaster45/Savage10FLP308-1.jpg[/img]

Sierra 168 gr HPBT on left and Lake City 173 gr FMJBT on right.

[img width=600 height=398]http://i218.photobucket.com/albums/cc265/pbcaster45/MexicanMatchM118.jpg[/img]

Here's how the test went.

Group #1 Foulers with Mexican Match (from a clean, de-coppered barrel)

Group #2&4 Unaltered M118 Match.

Group #3&5 Deep Seated M118 Match.

Group #6 Five rounds of Mexican Match.

[img width=600 height=398]http://i218.photobucket.com/albums/cc265/pbcaster45/MixedGroups.jpg[/img]

[img width=600 height=398]http://i218.photobucket.com/albums/cc265/pbcaster45/MexicanMatch.jpg[/img]

With this lot of ammo (in this rifle) it looks like Mexican Match is a waste of time. I do think deep seating improved accuracy and consistency. Now if I can just find that last 50 rounds of M118 I will run the test again with freshly broken neck sealant.

**Note** The powder in the M118 Match looked just like IMR-4895 and weighed an average of 41.8 grs.

Considering IMR 4895 was developed for 30cal military rounds, what you found doesn't suprise me at all.
I have found loads for everything I shoot with it and now that is all I use. Yes I loose some velocity but my accuracy more than makes up for it out to 200yards, that is the furthest I can shoot around here. I would love to find a place to shoot further but none is available.No I take that back there is a 350 range but no openings for new members and the guys there don't like quest.

Target #6 was the tightest group...sans one flyer.

Redo the test at 200 or 300 yards....THEN pick the winner.

Didn't know that match ammo had neck sealant...

Learn something new every day.

No doubt substituting the Sierra HPBT is the most accurate way to go... but the time involved? I'll stick with breaking the neck sealant. If I can find the rest of my stash I will test it at 200 yards and chronograph it too.

Eric, it's military match ammunition - you won't find neck sealant on the regular commercial stuff.

Oh I knew that - just never noticed neck sealant on my 06 FA match ammo - guess they started putting it on the 308 stuff (why?).

Why? The rigours of war, that's why.



Hutch

I was using the same match ammo to break in my F/TR when i first got it had the same accuracy with it as you did.

Quote:

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Originally Posted by pbcaster45

No doubt substituting the Sierra HPBT is the most accurate way to go... but the time involved? I'll stick with breaking the neck sealant. If I can find the rest of my stash I will test it at 200 yards and chronograph it too.

Eric, it's military match ammunition - you won't find neck sealant on the regular commercial stuff.

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The new M118 LR has no sealant nor crimped primers and uses the 175 SMK. so i don't think mexican match would do you any good at all if using newer ammo.

Gary

Yep, all just for fun and to learn a little history!