New US Military .300 Win Mag Match MK 248 MOD 1

FYI im loading 208 amax to 3.520 (89.5mm), 77 grains H1000, 22 inch barrel, 2695 es 10. (factory weatherby mag box seems to be 90.5mm)

I cant figure out why its so slow, but I guess ill try retumbo, just ran out an hour ago of H1000.

Chris

Any signs of high pressure? Anything more than flattening of the primers?

I'm loading Berger VLDs with up to 77 grains so far in a 26" barrel, Rem 700 5R - and am getting good groups with OCW testing so far , will chrony the low and high nodes later - if I recall correctly, Hodgdon shows loads to 78 grains with these, a friend shoots 208 grain A-max out of a Winchester at 2950 but it's from a 26 inch barrel too.

Those four inches make a lot of difference.

Being so much closer to OZ, is it any easier to get Hodgdon powders?
 
Yes PACOM, we have been getting new toys at a pretty steady flow lately. ;)

Bryan- Thanks always for your contributions.

Havoc- Are the 2010's and 110's your only sniper systems, plus probably Barrett's? I haven't heard anything about having to turn our 2010's in but we only got them a few months ago and are currently deployed so maybe that is why. I wonder if it is a recall or an upgrade going on with yours...
 
My speculation on the reg match primer is that the regular one gives a lower extreme spread and standard deviation. That's how it worked out in my 7 Mag.

I will agree with that. Dipped my toe in the pool last week, 77gr H1000 loaded under 220smk to 3.5" oal with CCI 250 primers 2902, 2893, 2914, 1.24"@ 200yds. Same load using CCI BR primers, 2883, 2882, 2888, .620" @200yds. Rifle is 29' Rock 5R barreled Rem700. Now just gotta find the sweet spot for those 230gr Bergers.
 
I've also found that standard large rifle primers produce better groups and lower SD than mag primers in 300 Win Mag, systematically, for a variety of powders.

H4831 and H1000 are good temp stable, single based powders to use with the heavy bullets. Magpro will get quite higher velocity, but as a double based powder, you can expect more temp sensitivity.

Some advice; load the 230's as long as your chamber/magazine/action allows. You want to be at least 3.6" COAL, longer if you can.

-Bryan
 
Interesting. I guess I'll have to figure out the difference between a secant & tangent ogive.

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: sandwarrior</div><div class="ubbcode-body">Chad,

Because there are more efficient bullets in 6.5, 7mm, and .338. As MontanaMarine noted, "I wish they would have looked past somebody besides Federal and Sierra." There are several designs out there that are far better than the 220 gr. Sierra bullet they specify. Berger 180's for example pushed at the same muzzle velocity get 150 more yds. of supersonic travel. And, FWIW, they do stabilize better I think than Sierra past supersonic range. I shot both at 4000 ft. elevation not sea level or where I'm at here at just under 1000 ft. But they went truer in flight and truer into the target.

I dunno, I should just be happy they decided to go with more potent 1k+ medicine than the 7.62x51. </div></div>
Sand,
I would agree, but we are talking an across the board caliber/load for many rifles. And all the rifles will need to shoot this load well. If you have ever played with the VLD's in multiple rifles, you will see they are very sensitive to seating depth, and are very finicky from rifle to rifle. The SMK is fairly predictable on how to load it and get good results. The secant ogive bullets, like the VLD, can take a lot of work to get to shoot well. They are not near as easy to get to shoot as the SMK, which has a tangent ogive. Once you find the sweet spot for the VLD in "your" rifle, it will out shoot any SMK, period. But for an across the board bullet, the SMK (IMO) is a great way to go.
And, again, cost is a factor. The VLD bullets will run about 10%-11% more in cost. Factor that over the millions of rounds of ammo, and it's a lot of dough.

I shoot a 260 Rem now, but shot my 300WM for several years in competition. The energy the 300WM offers over any of the 6.5 calibers (and almost all of the 7mm loads) is huge. When you see it hit steel at extended ranges, you understand this energy. The .338 is a good option, but not in the 338 Win Mag. You have to go to the 338 Lapua or bigger to improve over the 300WM. And one of the goals of this venture was to reduce the cost of ammo. The 338 Lapua is a much more expensive option.
 
I'm still trying to grasp the concept that the military wants a longer range sniper rifle, but instead of going with the 338 Lapua, they decide on the 300 WM...? If what you want is the ability to "go long".....then why not do it right & get the best available system.....maybe even skip the .338 Lapua all together & upgrade to a .375 Cheytac.

I've heard the argument that the other rounds "cost too much" so that's why they are going with the 300 WM.....really...? Cost too much...? The US just lobbed 110 Tomahawk missles at Libya, basically a "blip" on the radar as far as military action is concerned. At $756,000 a piece that's roughly about $83 million bucks.

Someone posted earlier that the military put in an order for 34 million rounds. Even if they paid $8 per round (which they wouldn't) for the better long range round (.338 lapua or .375 Cheytac), we're talking about $170 million in spending. I seriously doubt that the military couldn't come up with a few extra hundred million to make it happen.....just seems like a "cop out".....
It's a different world now, budgetwise. It's not so simple to just do this or just do that, which might lead to a better weapon system - changing out some M24 barrels to 300WM (as the M24s were designed to do long ago) is probably much easier to accomplish than a new rifle acquisition when we're out of Iraq and about to leave Afghanistan. This is going to be the new reality in general (and those Tomahawks are already paid for).
 
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I've also found that standard large rifle primers produce better groups and lower SD than mag primers in 300 Win Mag, systematically, for a variety of powders.

H4831 and H1000 are good temp stable, single based powders to use with the heavy bullets. Magpro will get quite higher velocity, but as a double based powder, you can expect more temp sensitivity.

Some advice; load the 230's as long as your chamber/magazine/action allows. You want to be at least 3.6" COAL, longer if you can.

-Bryan

I recently got a #50 Keg of H4831 surplus powder unopened for $25 at a estate sale. Powder was stored properly and is good to go. My question is does anyone have data with H4831 and the 220gr SMK or the 230gr Berger. I have both bullet types and will be loading for a custom .300 WM thanks.
 
I'm still suprised that Crane is using a standard SAAMI 300 win mag reamer with no change from Mod 0 to Mod 1.

I kinda figured PTG would have a unique reamer for the Mod 1 version.
 
I've also found that standard large rifle primers produce better groups and lower SD than mag primers in 300 Win Mag, systematically, for a variety of powders.

H4831 and H1000 are good temp stable, single based powders to use with the heavy bullets. Magpro will get quite higher velocity, but as a double based powder, you can expect more temp sensitivity.

Some advice; load the 230's as long as your chamber/magazine/action allows. You want to be at least 3.6" COAL, longer if you can.

-Bryan

Bryan, does this hold true for H1000? I am wondering if I should try the F210M's that I have, instead of the CCI 250's currently loaded.
 
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I've also found that standard large rifle primers produce better groups and lower SD than mag primers in 300 Win Mag, systematically, for a variety of powders.

H4831 and H1000 are good temp stable, single based powders to use with the heavy bullets. Magpro will get quite higher velocity, but as a double based powder, you can expect more temp sensitivity.

Some advice; load the 230's as long as your chamber/magazine/action allows. You want to be at least 3.6" COAL, longer if you can.

-Bryan
Bryan,

Could you please comment on the temperature sensitivity of MagPro? What in your opinion/experience would the temperature range be (e.g., if the load was chrono'ed at 70F)?

Thanks!
 
Isn't Retumbo a part of the same "exteme" line as Varget and H-1000? So it shouldn't be very temp. sensitive. I've heard of Retumbo being pretty spiky as far as pressure goes once you start to increase a charge.

I use Retumbo in my 208 A-Max load and it shoots great! 3,000 fps with no pressure signs!

I plugged it into JBM and my round will stay supersonic to 1700 yards.

That has me thinking they are getting that 220 SMK moving!!


the 208 has a better BC then the 220 and should move faster... not to mention the Amax F's stuff up when it hits... the SMK's can be vary hit/mis on soft targets
 
they didn't change anything I know of, it's still the same rifle used for the A191, or Mk248 MOD 0...

These are from Crane (Mk13), so nothing has changed yet, most are still fielding old rifles with new ammo.

The new M24E1 that was recently awarded might be different, but right now, nothing has changed.

Look at the AI AW, no pressure signs and manageable velocities, these chambers are not cut to Bench Rest Tolerances, but much looser to allow for dirt and debris. The AWM works fine, no adverse affects.


And the AWM has been fielded with the German Army as the G22 rifle for a long time using a stout load,..nothing new here.
 
The biggest question I have, and it may be trivial. Why would ATK (contract winner for this ammo) use H-1000 when they make Reloader powder? Just seams odd that they wouldn't want to keep it in house as much as possible.
 
Blackhills developed the load at it's own expense. Shipped a quantity to Crane for testing and load was excepted.Then Govt puts out a solicitation for said load. All load development was done all, ATK had to do was load it to spec. Talk about a no brainer for ATK. I know it's the free market at work but it would seem to me the govt should throw the company that developed the load a bone and give that company the first contract.
 
Finally got around to getting a 300 wm built, a Krieger MTU 26 5r hanging off a Stiller TAC 300. This has been an informative thread. I have a couple thousand 190 smk's and a thousand 220 CC pills but my brass is mil once fired, cant find new brass to buy, leaning towards Norma right now which is scarce. I went back and forth between the 338 and the 300, this thread convinced me to go with the 300 WM. Again thanks gents.

Chad Dixon LRI doing the work, Bugholes provided the barrel and action.
 
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SPECTRE 004.JPGRecent build on Stiller Spectre Action, LW poly barrel. Shoots 1/4 MOA with Berger 190 VLD. Built by Mike Norris at "Brock & Norris".
 
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Finally got around to getting a 300 wm built, a Krieger MTU 26 5r hanging off a Stiller TAC 300. This has been an informative thread. I have a couple thousand 190 smk's and a thousand 220 CC pills but my brass is mil once fired, cant find new brass to buy, leaning towards Norma right now which is scarce. I went back and forth between the 338 and the 300, this thread convinced me to go with the 300 WM. Again thanks gents.

Chad Dixon LRI doing the work, Bugholes provided the barrel and action.

I went a similar route, Stiller TAC300 with a 26" Bartlien M24 contour. I've worked up a load using Hornady brass and the Berger 230 OTM. 77.3 grains of H1000 is giving me 2930fps. Advise caution as I'm over book max. I also went back and forth between the .300 and .338. Brian Litz's book helped convince me on the .300. O'yea, Chad also did my plumbing.
 
Yes the OTM load used H1000 I did not find the powder charge but the 230 OTM suppose to be better on the throat than the 220 MK and increase effective range.

The Mod 1 is loaded very hot ......I cannot dupicate it.
 
I've also found that standard large rifle primers produce better groups and lower SD than mag primers in 300 Win Mag, systematically, for a variety of powders.

H4831 and H1000 are good temp stable, single based powders to use with the heavy bullets. Magpro will get quite higher velocity, but as a double based powder, you can expect more temp sensitivity.

Some advice; load the 230's as long as your chamber/magazine/action allows. You want to be at least 3.6" COAL, longer if you can.

-Bryan
I got great results with CCI BR2's and H1000 in my .300 as well. In fact I kinda miss it but now I have a .338 edge which will not work well with br2's
 
New US Military .300 Win Mag Match MK 248 MOD 1

I did some testing this past weekend with my 300 wm and shooting the 208 and 230 OTM here are my results and the testing was done at 300 yards.
I don't believe in testing at 100 as typically most rifles are capable of nearly one hole groups in the right hands. You don't get the opportunity to see vertical in those groups unless you test at 300-500 yards.

Below are my results

ImageUploadedByTapatalk1411951899.418190.jpg

ImageUploadedByTapatalk1411951929.316194.jpg

ImageUploadedByTapatalk1411951943.639765.jpg
 
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The 230gr Bergers and H1000 are good, but the older 208AMAX with the same powder is phenominal. This is an honest 1000yds. Stiller with a Bartlien tube. I worked up the same load (to the exact same 76.0gr) with the 208ELDm but haven’t taken it out to distance yet. Close in they appear identical with a bit better numbers far out. We shall see. The 230 Berger load (@about 2950fps) was really hard on brass. The 208s seem much easier.
 

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