mk248 mod 1 ammo

*greenhorn*

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Re: mk248 mod 1 ammo

as long as its a 300 win mag chamber, The US government purchased MK 248 MOD 1 .300 Winchester Magnum match-grade ammunition in 2009 for use in adapted M24 Sniper Weapon Systems and other .300 Winchester Magnum sniper rifles like the US Navy Mk.13s. This ammunition was developed as a .300 Winchester Magnum Match Product Improvement (PIP) and uses the 14.26 g (220 gr) Sierra MatchKing Hollow Point Boat Tail (HPBT) very-low-drag bullet fired at a nominal muzzle velocity of 869 m/s (2,850 ft/s) ± 15.2 m/s (50 ft/s). According to the US Navy this ammunition should increase the maximum effective range of .300 Winchester Magnum sniper rifle systems to 1,370 m (1,500 yd), decrease wind deflection on bullets in flight and use a reduced muzzle flash propellant that remains temperature stable across an operational temperature range of -32 °C to 74 °C (-25 °F to +165 °F).[
 

Gray

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Re: mk248 mod 1 ammo

Most people that have tried to fire this ammo out of their rifles have had huge pressure signs because the MK 248 Ammo is maxxed out with around 77-77.5 grains of H1000. The military rifles that are designed to use this ammo have a special chamber that allows it to be fired at around 2850 fps. Some folks have shot it through their rifles and have had results around 2970-3000 fps which is way to fast for a 300 win mag pushing a 220 SMK.
 

*greenhorn*

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Re: mk248 mod 1 ammo

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Special Delivery</div><div class="ubbcode-body">Most people that have tried to fire this ammo out of their rifles have had huge pressure signs because the MK 248 Ammo is maxxed out with around 77-77.5 grains of H1000. The military rifles that are designed to use this ammo have a special chamber that allows it to be fired at around 2850 fps. Some folks have shot it through their rifles and have had results around 2970-3000 fps which is way to fast for a 300 win mag pushing a 220 SMK. </div></div>

?? unless im crazy

im throughing 208 amax at about 3000+ with 73.5 Vihtavuori N560 out of a rem 770 300 win mag, i garentee the 700 built better than the 770. if in question pm lr-wsm he has shot the gun him self

according to quick load, with 77 thats 102.4% case fill of h1000 i doubt very seriously you could fit it in the brass with out any spilling over, so i went to the press on a 300 twice fired brass i can only fit 76.3 of h1000 and have enuff room to comfortably press a 208 amax in to it. and a 220 is longer by a few .01"s of a inch.

 

Km22

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Re: mk248 mod 1 ammo

i had a box and took it to the range and on the third bullet, i had to smash the bolt with something to get it back open. i had a feeling it was the ammo, but i installed a jewell trigger as well and didn't know if that had anything to do with it.
 

winxp_man

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Re: mk248 mod 1 ammo

I would not run that ammo in your rifle unless you have a really long headspace chamber. I have shot some 220 SMK with H1000 powder @ 77.0 grains. They are a tad bit hot. Not worth running. I run my Remington 700 Sendero SF II with 76.0gr and get really nice numbers I'm in the 2830-50 FPS. 77gr of h1000 is what the military needs but the chambers are longer. So for them 77gr is not really an issue. Plus hotter loads only eat up your barrel faster.

Oh and my load is in the .419 and the smallest group I was able to shoot was .305 not bad I guess
smile.gif
Also my loads are all 3.550 COAL.



Aron-
 

*greenhorn*

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Re: mk248 mod 1 ammo

i see i will look at it later again, maybe it was me with the h1000, i use Vihtavuori N560 in my 300 wm i will remeasure after i have read that.

thank you

I will tell you this that 300 wm is my you talk shit gun, i have a diffrent gun, but you talk crap i hand you that 8.5 pound gun with the 208 in it, ask lr-wsm, it mess you up with that scope pushing that projectile that fast!