Mk 13 Mod 0 stock

[pmclaine]

Funny how no one walked into Winchester and did the same? Or, Savage, Or Marlin? They all had deals made before transferring to the Gov't.

Oh but they did.

Lots of Remington Model 11's with duck engravings got a bursting bomb ordinance stamp and became riot guns or aerial gun trainers.

If it wasn't federal govt taking inventory it was state govts taking whatever was on the shelf to supply their police forces.

The owner of my gun honey hole had the opportunity to get some 1000 or more pre WWII, new in the box Colt revolvers in some obscure caliber during the 1970s.

The State Police had bought them from Hartford when the war broke out and they never used them. He couldn't get them because the state had no means to accept cash from him. The State Police wanted a trade of holsters, radios and other police gear in kind which he had no access to.

Just about everything that was available in manufacturer inventory was locked down by some govt entity, perhaps even just before, but in anticipation of, hostilities.

 

[sandwarrior]

My point with Winchester was they couldn't seem to give away their M70's. A great rifle for sure. As proven through history. Their model 12's weren't seized right away, either. Eventually they were.

 

[pmclaine]

My point with Winchester was they couldn't seem to give away their M70's. A great rifle for sure. As proven through history. Their model 12's weren't seized right away, either. Eventually they were.

Winchester was up to their eyeballs producing Garands and the carbine was their design I think. They made a few shotguns too.

I've heard an anecdote about the mil looking for the best sniper rifle seeing what they could do with the A4, M1941 and a Garand variant.

For the test a Win M70 bone stock was acquired as the baseline comparison. The mil rifles were worked over by the Armory.

When the test was done the evaluator was asked which rifle performed best and he said "Get the Winchester".

Dont know if its true or not but it's a good story told to me by someone knowledgeable.

 

[sandwarrior]

That's not so much an anecdote, as it is for the most part true.
The deal is when Winchester offered their model 70's as sniper rifles, the Bureau of Ordnance wasn't interested. Not until after the war started did they finally accept them, March of 1942. The M1 contracts started in April 1941 for the 500 educational lot, and May of 1942 for the first 65,000 combat lot. Building the line for the combat lot took time, but most of the dedication there was emplacing and setting up the line. Not really detracting from the M70 line, which didn't do anything special for production. They were handed over just like they went out the door as civilian rifles. The point in this is they were not swamped. They offered up their rifles. The Navy came in and dictated the 720's would go to them.

 

[NukeMMC]

And to get things back on the track of MK13s:
https://dsgarms.com/mk248-mod-1-can

 

[FatBoy]

$2.30 a round. Holy shit.

I haven't seen any targets from Buffalo yet. The 300wm too much for the 300y indoor range OR is Texas being hotter than the surface of the sun curtailing you're mk13 break in? Inquiring minds want to know....

 

[NukeMMC]

$2.30 a round. Holy shit.

Well, for those looking to shoot THE correct ammo out of a MK13 clone, this is IT. You won't find commercial ammo pushing a 220gr SMK at 2850fps +/- 50fps MV at 70F. I have seen 220gr Atomic advertised at 2600fps. ABM 230gr Hybrids come close at 2800fps.

I would NOT recommend anyone shooting MK248 Mod 1 thru a chamber not specifically cut for this. As it is, the chamber pressure for MK248 Mod 1 is supposed to not exceed 68,100 psi where the SAAMI spec is 64,000 psi.

 

[FatBoy]

I guess if you don't reload, this is the option. Not sure m248 Mod1 chambers are commercially released beyond longriflesinc. I would NOT shoot this shit out of a match chamber.

FWIW, 2775-2800 with 230OTMs is pretty easy in an A191 chamber. I have six firings on Winchester brass and it's still holding primers. Lost 3 to neck tension and had to drop a bushing size after the 3rd firing but it it's still going. Trick for me was Retumbo. H1000 just didn't shoot in my barrel.

 

[sandwarrior]

It's the leade/freebore you have that will or won't alleviate pressure. From what I know Mk248 mod 1 is NOT SAAMI approved. Nor is it rated to 68k psi. SAAMI does test for various entities, like the military. But, when they test, it's done in it's prescribed chamber. That is with the changes from the basic chamber spec. Mk248 mod 1 would be a helluva lot hotter in a chamber with no freebore than 68k.

One has to think here of total pressure. A 5.56 that is rated at 62k max, in it's own chamber, not a
223, often shows signs of pressure. That total pressure is based on volume as well as burn speed of the powder. A Mk248/.300 WM is four times the volume of a 5.56. The total pressure is right about what steel can hold if you don't alleviate it. The last I heard it, they were still capping pressure at 60k.

Correction:. SAAMI shows 64k psi via transducer. Transducer is the more accurate method of measurement. I was thinking C.U.P. still.

 

[NukeMMC]

It's the leade/freebore you have that will or won't alleviate pressure. From what I know Mk248 mod 1 is NOT SAAMI approved. Nor is it rated to 68k psi. SAAMI does test for various entities, like the military. But, when they test, it's done in it's prescribed chamber. That is with the changes from the basic chamber spec. Mk248 mod 1 would be a helluva lot hotter in a chamber with no freebore than 68k.

One has to think here of total pressure. A 5.56 that is rated at 62k max, in it's own chamber, not a
223, often shows signs of pressure. That total pressure is based on volume as well as burn speed of the powder. A Mk248/.300 WM is four times the volume of a 5.56. The total pressure is right about what steel can hold if you don't alleviate it. The last I heard it, they were still capping pressure at 60k.

Correction:. SAAMI shows 64k psi via transducer. Transducer is the more accurate method of measurement. I was thinking C.U.P. still.

From the MK248 Mod 1 Detail Spec:

 

[NukeMMC]

I guess if you don't reload, this is the option. Not sure m248 Mod1 chambers are commercially released beyond longriflesinc. I would NOT shoot this shit out of a match chamber.

FWIW, 2775-2800 with 230OTMs is pretty easy in an A191 chamber. I have six firings on Winchester brass and it's still holding primers. Lost 3 to neck tension and had to drop a bushing size after the 3rd firing but it it's still going. Trick for me was Retumbo. H1000 just didn't shoot in my barrel.

Yeah, I was getting 208 AMAX to 2900fps and 190s were at 3050fps in my A191 chamber (A191 is the NALC/DODIC for MK248 Mod 0, AB43 is the NALC/DODIC for MK248 Mod 1). The 208s were with 77.0gr H1000 while the 190s liked RE22 better.

AJ Brown did my A191 chamber back then (2011). PTG sells a Navy MK13 reamer.

 

[sandwarrior]

From the MK248 Mod 1 Detail Spec:

Those are the maximum allowable at the intended temperatures, not the intended target pressures. The "Do Not Exceed" if you will. If something happens in the machine and a case gets too many grains of powder, the 68k is the most you should end up with. Testing is done once the ammunition is assembled to see that it doesn't exceed that. Average, should be no more than 60K psi. There are better ways to increase velocity, than yanking up the pressures on ignition.

Again, too those pressures are in the chamber cut for that round not the standard .300 WM round. So, even still, they are hotter than standard .300WM

Edit: Added: I was getting 2930 with 208's and Berger 210's using 75.1 gr. of H1000. Different chambers I suppose. I tested all the way up to 78.8 gr. but had pressure signs above that. The book goes to 80~.something. There are a lot of differences when loading a belted magnum. I also seated the 210's (first) then later the 208's to the lands.

 

[spooledup]

Just posted some 220gr SMK's and Black Hills brass in the Reloading FS section.

 

[sirhrmechanic]

And to jump in late to this part of the discussion... I think handloading is the only way to go with these rifles. First, the factory ammo is stupid expensive. Second, you can get so much improvement in consistency by working up your own load and using neck-sizing on the brass after the first firing. I have no doubt that the builds will be excellent whoever does them. But as with most rifles, the cartridge is going to matter. And for price/performance, nothing is going to beat handloads.

Cheers,

Sirhr

 

[buffalowinter]

OK, went out and test fired the Mk13 Mod 0 with Seal return stock , Lilja barrel, and Nightforce NXS scope. [IMG2=JSON]{"data-align":"none","data-size":"full","src":"http:\/\/i.imgur.com\/9uvGZw6m.jpg"}[/IMG2]




Very good results. Shooting at 100 yds in a light wind and 100 degree heat, I fired ten rounds fouling/sighting shots to get on target. Then I fired a 10 round group using Federal Gold Medal Match. Not bad, as I was firing fairly quickly and more interested in function testing the scope and rifle. No problems. Next I fired five shots with a hand load of 190 g Sierra Match King BTHP loaded with 70.3 g of RL 19. This is the load the Army uses. Very nice sub moa group holding a little tighter. Last five shots I bore down and shot for a good group...rounds 25 through 30 of the brand new Lilja Seal return barrel...using 210g Berger VLD Target with 77.0 g H1000, yielded a .557 EDGE to EDGE group, which is about .25 moa. Stopped there with a total of 30 rounds through the barrel. Couldn't be more pleased. [IMG2=JSON]{"data-align":"none","data-size":"full","src":"http:\/\/i.imgur.com\/9WU8xCwm.jpg"}[/IMG2]

 

[sirhrmechanic]

That's some good shooting there, Tex! Nicely done!

Actually, better than I expected from the combination. Though I suspect you poured a lot of extra time and attention-to-detail into this project.

Congratulations! Can't wait to get mine back.

Cheers,

Sirhr

 

[FatBoy]

That's a good day, especially if there was no brake or can on that rifle. They are a heavy stick but 210s over 77gr of powder is no shit. That had to get your attension. Glad to see some results. Hopefully by Christmas we have 2-3 pages of groups and field reports. So good to see these kits live on.

 

[buffalowinter]

You know, I don't find the recoil too bad. The gun weighs a ton (16 3/4 pounds actually), has a thick recoil pad, and is ergonomically suited to absorbing recoil. Admittedly, I was shooting off a rest on a bench, and I had a shock absorbing shoulder pad on for when the rest recoiled into my shoulder. I use a very light trigger, 2 lbs, and just don't notice the recoil too much. For a tactical rifle where you will take one shot, maybe two, before displacing (hopefully), recoil just isn't that big a deal for me (I know modern doctrine on when to displace has changed). Certainly, for me, shooting an International Full Course of a 120 shots of .308 at 300 meters over the course of 3 1/2 hours is far harder.
[IMG2=JSON]{"data-align":"none","data-size":"full","src":"http:\/\/i.imgur.com\/8mRSFBXl.jpg"}[/IMG2]

Internationale Match Woche 1981 Zurich, Switzerland

 

[FatBoy]

I agree, shoot and move, shoot and move, shoot and go get breakfast before the mortars start dropping. You've done a ton of shooting so I assume you don't suffer my affliction, a condition commonly called "recoil pussy". The can dramatically helps.

With only 30 rounds down the pipe you have to be tickled. I couldn't find any 210 Bergers or SMKs when I started testing. The 230 OTMs shot so well I stuck with them but I think a 210 really is probably a better fit with the 1:10. Should strike the right balance between BC and weight/length.

 

[sandwarrior]

Buffalo,
Thanks for posting back! Love the groups and rifle. I noted you said the Army is using the 190 SMK still. Is that a variant of A191? Or , is it it's own special thing?
Also, is that the AMU? I understood a favorite of SOC operators was the 230OTM. While the rest of the combat Army is using the 220 SMK.

 

[buffalowinter]

[FONT=georgia, serif]I researched load data a while back when I started this project and made up this load with a note that said "Army load". I can't remember where I sourced that data and whether it was an AMU load developed for sniping or a special contract.[/FONT]

 

[NukeMMC]

I researched load data a while back when I started this project and made up this load with a note that said "Army load". I can't remember where I sourced that data and whether it was an AMU load developed for sniping or a special contract.

I remember shooting against/with the AMU guys at Benning, Gordon and Blanding on some mid-range and LR matches in the early 90s. Their magnum ammo was not Federal, like their gas gun ammo. It appeared to be home-brewed in plastic ammo boxes like what we use. I also remember them using 40x short actions. The rounds barely fit in single-loading but the empties ejected fine. If they had to pull a live round out (which they did at Blanding KD-A once when a 8+ ft diamondback made his way across the front of the berm at 600 and we had a ceasefire in preps for folks needing to move in haste). At that point they pulled the bolt and dragged the round out.

 

[buffalowinter]

More range tests of the Mk13 Mod 0. The first five shots were from a cold bore and the flyer to the left I called. It was interesting to note very little change in point of impact from different powder and bullet weights. The gun seems to like H1000. The 220 g SMK's yielded a nice .5 moa group but the 210 Berger VLD Target with 77.0 g H1000 seems to yield the best results. Primers were a mix of Federal match and Winchester. Had two failure to fires with the Winchester. Brass, interestingly enough, was the inexpensive PPU, but I had no complaints with sub .5 moa groups.

[IMG2=JSON]{"data-align":"none","data-size":"full","src":"http:\/\/i.imgur.com\/4SNEodpl.jpg"}[/IMG2]

 

[sirhrmechanic]

SNIP Their magnum ammo was not Federal, like their gas gun ammo. It appeared to be home-brewed in plastic ammo boxes like what we use. SNIP .

Here's a picture of one corner of the USAMU's handloading facility.... Home brewed indeed!

At one point, there were a couple of interesting handloading shops within the perimeter of Ft. Bragg, too. Wonder if they are still around?

Back to Buffalo's loads... looking very good there! I have a lot of 220's that I have picked up. Only a handful of 190's. I am hoping I can put together a good load with 220's. I've not loaded H1000 before, but given your results, that also looks promising. I was going to use 4350... but can't complain about the results from the H1000!!

Cheers,

Sirhr

 

[buffalowinter]

Just a correction...the bullet that gave the best results in my rifle was a Berger 210 VLD Target, not Hybrid Target. I've gone back and corrected the original posts.

 

[sandwarrior]

Here's a picture of one corner of the USAMU's handloading facility.... Home brewed indeed!

At one point, there were a couple of interesting handloading shops within the perimeter of Ft. Bragg, too. Wonder if they are still around?

Back to Buffalo's loads... looking very good there! I have a lot of 220's that I have picked up. Only a handful of 190's. I am hoping I can put together a good load with 220's. I've not loaded H1000 before, but given your results, that also looks promising. I was going to use 4350... but can't complain about the results from the H1000!!

Cheers,

Sirhr

A part of me wonders why so many dies for mostly one cartridge. Then I realize each rifle is different and needs to be set up specifically for that rifle.

Buffalo,

Were you loading the 210 VLD Target bullets into the lands? I had found with other, smaller diameter, bullets that loading into the lands was how to peak out on accuracy. I found that the .30 Cal. bullets didn't have too much of an issue with that.

 

[sirhrmechanic]

^^ Plus the AMU shoots a lot of different stuff. .223 .300, .30, shotguns, .45's, 9mm's... they compete in everything... skeet, trap, ipsc, three-gun... AMU is about promoting the U.S.A. brand, developing new cartridges and techniques, etc. But they are like a racing team... or the Golden Knights... or the U.S. Army Band. They have an 'internal' purpose, but getting out there and competing at the highest levels in all kinds of different venues more than pays their bills in marketing value.

So their reloading shop is a candystore. They have a blog called 'Handloading Hump Day" every Wed. It's worth following. They really are the varsity, not just on the range, but in the 'lab' so to speak.

Cheers,

Sirhr

 

[sandwarrior]

Makes me wonder if they still keep a few .30-338's around.

 

[buffalowinter]

Sandwarrior, that's not that many dies.

My best shooting load, 77.0g H1000, 210g Berger VLD Target, has an OAL of 3.646" which is just off the lands, My second most accurate load of 74.0g H1000, 220g SMK #2240, has an OAL of 3.340" to allow it to feed through AI/Magpul magazines.

 

[Triggered]

I may be stealing some of yall's load data once my gun gets together. Buffalo's results look very promising.

So I snagged a no prefix 700 for a super price, but I couldn't force myself to use it as the donor gun. The thing was too clean for its age (a '72 I believe) and the trigger had been worked to maybe a pound. It's for sale.

Ended up getting a little rougher B prefix for an even better price and it will surely work for the build. Spoke with Alan on the phone and although the C prefix is popular, he vouched that B series and even later receivers were used, so I didn't feel any pitty using a B.

Was at Mile High maybe a month ago snooping around and they actually had two police trade in NXS scopes that were the proper spec and one was a damn near match to the paint on my stock, so I grabbed it.

Still about 4 weeks (I hope) out on the barrel from Lilja has I've heard they're getting them out in about 8 weeks time. Going to thread mine with the run of the mill 5/8x24 and have a muzzle device on it despite authenticity deviation. I planned on direct threading my silencer, but Alan convinced me to do otherwise and use a muzzle device. Going to stick with the bead blasted finish I believe.

Should be good to go once the barrel comes in; off to Alan and start the timer from there.

 

[sandwarrior]

Kind of off topic here, but what was the RR prefix? Was that new purchase for A-5's?

 

[grunt0311]

The RR prefix was used for the new M40a6 short action. I also think that they were used for the MK13 Mod 5 as well just in long action. I have some pics that show the SN for the Mod 5.

 

[sandwarrior]

The RR prefix was used for the new M40a6 short action. I also think that they were used for the MK13 Mod 5 as well just in long action. I have some pics that show the SN for the Mod 5.

The reason I ask is I saw one at a gunstore in .308. It was a short action in what looked like an A-5 stock. I didn't remember if we had talked about RR s/n's on here or one of the M40A-1/3/5 threads.

 

[grunt0311]

I don't think that the SN have been talked about much on this thread. We all know that the first one's were C prefix SN but we haven't talked much about the later models.

 

[jmar]

I 2nd gathering more info on SN prefixes, with these rifles theoretically you could make an exact replica because they were not stamped like other military rifles were right? Like the M24's say M24, do the Mod 0's say anything or are they just plain Remington long actions?

 

[FatBoy]

Jmar,

unless photobucket fucked up the links, there are pics of the engraving on the bolt body and how the serial numbers were transferred to the bolt handles further up in the thread. To my knowledge (limited at best) the Mod7 was the only mk13 that had a receiver body engraved with mk13, but don't take that to the bank.


Edit: posts 411 and 412 still have photos showing the bolt engraving and serial transfer.

 

[crawdad1]

My mk13 thanks to Accurate Ordnance for the fresh barrel.

 

[sandwarrior]

My mk13 thanks to Accurate Ordnance for the fresh barrel.

Somebody needs to come along and say that's a nice rifle crawdad.

 

[crawdad1]

Thanks

 

[FatBoy]

Curious to hear how it shoots. I have heard AO builds are shooters. Did you go with the A191 chamber?

 

[crawdad1]

I haven't shot it much but so far it looks promising. Yea I debated having it throated for the 220gr military load but kept it original.

 

[FatBoy]

It will likely still shoot the 208-230s with hand loads. I have found the Berger OTMs to be very forgiving with jump.

 

[crawdad1]

I've heard good things about the 230s may give them a shot.

 

[8208]

This thread needs some fresh content. I got to take my Mod 0 out today after getting it barreled. The gun performed adequately when I did my part. The trigger needs a little work as it is heavy right now. I have a bucket of 210's that I am going to work up for it and another Win Mag. Don't tell the clone police that my Mod 0 has a Mod 5 barrel! It was free and new and does the same job!

 

[RWSGunsmithing]

This thread needs some fresh content. I got to take my Mod 0 out today after getting it barreled. The gun performed adequately when I did my part. The trigger needs a little work as it is heavy right now. I have a bucket of 210's that I am going to work up for it and another Win Mag. Don't tell the clone police that my Mod 0 has a Mod 5 barrel! It was free and new and does the same job!

The Mod 5 barrel is clone correct for a late mod 0.

 

[8208]

Thanks! I learned something today.

 

[Triggered]

Nice looking stick there, Bates. Love the color of it.

Lilja barrel is showing up tomorrow for my rifle. Think I ordered it around 4th week of June, so pretty much on the money with their wait times. I had heard some were getting theirs quicker.

Everything should be heading off to AJ Brown once the green light is received, then a big ol' wait to be had there as he assembles it.

Has anyone had good success with Hornady ELDs in their Win Mag?

 

[8208]

Thanks. She was painted when I got it. I just took some netting and some rattle canning later for the barrel. I haven't tried them. Bergers and Sierra's have been my go to for my others. Can't wait to see yours when it is finished. I hate that most of the pictures people posted have been lost due to photo bucket...

 

[buffalowinter]

For anyone interested, my first Mk13 Mod0 clone, discussed earlier in this forum, is for sale in the Firearms for Sale Forum of the Hide. This is the gun using a Grayboe Renegade stock before I went crazy and bought a SEAL return stock. Bargain priced at less than the total cost of the components...$1300. Pics, with groups and details, in the For Sale Forum.
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[IMG2=JSON]{"data-align":"none","data-size":"full","src":"http:\/\/i.imgur.com\/vGra2s3l.jpg"}[/IMG2]

 

[USMCSGT0331]

Just dropped an original Mk13 stock in the accessories section of the PX