MK262 Black Hills anyone successfully clone it?

[Canuckenstein]

So I have 100 volume sorted LC once fired swaged primer pockets,flash hole uniformed, pocket uniformed, trimmed chamfered and debured. They are all primed with S&B SR primers. I have several powders Ramshot TAC and BL-C2 seem to be the closest to a pulled and weight checked round. I sorted Base to ogive. Some 77gr SMKs. My question is anybody else using a different powder for this load. What were your results? SD,ES and Group size?

These will be fired from a PRI SPR MK-12 Mod0 upper on a Diemaco Lower. Hopefully I’m not beating a dead horse here.

 

[jmm03]

Canuck,what is the speed of the round in question, and how about a pic of your MK12. Jim

 

[Canuckenstein]

Canuck,what is the speed of the round in question, and how about a pic of your MK12. Jim

Advertised 2750fps for MK262. I am a Boilermaker and am working away from home. I will try to remember a pic of my rifle when I get back there in a month or so. But here’s a link to manufacture site. That’s my girl. I also may shoot these from my factory Colt M4 expanse.

https://www.precisionreflex.com/Detail.aspx?PROD=1046643&CAT=4824

 

[FatBoy]

I have done a ton or research on this and I can't figure out what Federal or BH are using. I'm guessing blended to pressure.

I run 24.x gr of either Varget or RL15 with no crimp. Once over 24 of either it's a warm load, hot above 24.3 but it's still not at hot as either M262 or FC262. Many use Ramshot TAC, though I haven't yet. My next try is AR Comp, worked up. Last time I tried it with a normal rl15 loading I lost 20 of 20 primer pockets.

Here's a buddy running one of mine a couple weeks ago. I love this platform. If I could only have one rifle for the rest of my life, this would be on the short list. Thankfully, we're not there yet.

 

[Canuckenstein]

I have done a ton or research on this and I can't figure out what Federal or BH are using. I'm guessing blended to pressure.

I run 24.x gr of either Varget or RL15 with no crimp. Once over 24 of either it's a warm load, hot above 24.3 but it's still not at hot as either M262 or FC262. Many use Ramshot TAC, though I haven't yet. My next try is AR Comp, worked up. Last time I tried it with a normal rl15 loading I lost 20 of 20 primer pockets.

Here's a buddy running one of mine a couple weeks ago. I love this platform. If I could only have one rifle for the rest of my life, this would be on the short list. Thankfully, we're not there yet.


View attachment 1042348

I know Johnny’s reloading bench on youtube did a series on mk262. Wanted to hear others results though. Fascinating that AR comp blew your primer pockets. Perhaps the secret is in the primers? Not the powder itself. If you watch vidjayo 6 of the clone of 262 you’ll see that Remington 71/2 primers IIRC gave 37fps faster muzzle velocity. Over CCI 41. Once I get sometime to get to the range I might fiddle with this theory. Using TAC and a variety of others. I also need to buy some more factory 262. To serve as my baseline on the day I chronograph my loads. Supplies of BH 262 at spotty at best as the canadian distributors are tools, and stores don’t like to deal with them. I am lucky enough to live 2 km from a range so once max charge of TAC is determined I can load it with some different primers.

 

[Canuckenstein]

Just realized I said AR comp not RL-15.

I know Johnny’s reloading bench on youtube did a series on mk262. Wanted to hear others results though. Fascinating that AR comp blew your primer pockets. Perhaps the secret is in the primers? Not the powder itself. If you watch vidjayo 6 of the clone of 262 you’ll see that Remington 71/2 primers IIRC gave 37fps faster muzzle velocity. Over CCI 41. Once I get sometime to get to the range I might fiddle with this theory. Using TAC and a variety of others. I also need to buy some more factory 262. To serve as my baseline on the day I chronograph my loads. Supplies of BH 262 at spotty at best as the canadian distributors are tools, and stores don’t like to deal with them. I am lucky enough to live 2 km from a range so once max charge of TAC is determined I can load it with some different primers.

 

[memilanuk]

Not Mk262 per se, but years ago there was a BH 75 BTHP load that was really popular with Service Rifle shooters, very similar specs as Mk262. Everyone said 24-ish of TAC. I did a normal load workup, from 23 on up past 25 gn, and all I got was lousy accuracy and over gassed to the point of dang near ripping the rim off. Velocity was way low, and ES/SD were all over the place. Some where along the line, someone mentioned crimping to alter the burn characteristics of the powder. Like most people, I'd always heard - and repeated - that you never crimp 'match' ammo.

Finally I went to pull five bullets of the factory ammo just to see what was in there. One, it sure as heck looked like TAC. I know that isn't definitive by any stretch, but just sayin'... Two, it was right on 24.2-24.3 gn. Three, and this is where it gets interesting... those bullets were in there hard. I mean, I couldn't even *budge* them with a kinetic puller. Finally went out and bought a press-mounted collet-style bullet puller. Even with that, I had to cinch it down to the point where the bullets were physically deformed - in no way reusable - to get them out. If they weren't crimped in there, they were the next best thing to it.

So... I got an inexpensive Lee taper crimp die - I think they don't make that one any more, but supposedly their current 'factory crimp' die does an equivalent operation and set it up in the press so it was just barely touching the case mouth. I loaded a few like that, then turned it 1/2 turn, loaded some more, turned it, loaded some more, etc. etc. Not sure I ever got quite brave enough to get quite as tight as that factory ammo had been, but definitely way more than I ever would have normally gone. Certainly more than I think I could have reasonably achieved by just using smaller neck bushings and/or no expander, not without having major issues with seating the bullets.

The range session... was enlightening. You could literally see on target as the groups tightened up as the crimp increased. What had been a 3-4" load worked its way down to 1/2 moa or better, with the velocity coming up and tightening up at the same time (sorry, don't have the notes anymore and I don't recall what the final velocity numbers were).

As I've been playing with my .223 Rems more, including a couple gas guns, I may have to work on recreating that load again...

 

[Canuckenstein]

Not Mk262 per se, but years ago there was a BH 75 BTHP load that was really popular with Service Rifle shooters, very similar specs as Mk262. Everyone said 24-ish of TAC. I did a normal load workup, from 23 on up past 25 gn, and all I got was lousy accuracy and over gassed to the point of dang near ripping the rim off. Velocity was way low, and ES/SD were all over the place. Some where along the line, someone mentioned crimping to alter the burn characteristics of the powder. Like most people, I'd always heard - and repeated - that you never crimp 'match' ammo.

Finally I went to pull five bullets of the factory ammo just to see what was in there. One, it sure as heck looked like TAC. I know that isn't definitive by any stretch, but just sayin'... Two, it was right on 24.2-24.3 gn. Three, and this is where it gets interesting... those bullets were in there hard. I mean, I couldn't even *budge* them with a kinetic puller. Finally went out and bought a press-mounted collet-style bullet puller. Even with that, I had to cinch it down to the point where the bullets were physically deformed - in no way reusable - to get them out. If they weren't crimped in there, they were the next best thing to it.

So... I got an inexpensive Lee taper crimp die - I think they don't make that one any more, but supposedly their current 'factory crimp' die does an equivalent operation and set it up in the press so it was just barely touching the case mouth. I loaded a few like that, then turned it 1/2 turn, loaded some more, turned it, loaded some more, etc. etc. Not sure I ever got quite brave enough to get quite as tight as that factory ammo had been, but definitely way more than I ever would have normally gone. Certainly more than I think I could have reasonably achieved by just using smaller neck bushings and/or no expander, not without having major issues with seating the bullets.

The range session... was enlightening. You could literally see on target as the groups tightened up as the crimp increased. What had been a 3-4" load worked its way down to 1/2 moa or better, with the velocity coming up and tightening up at the same time (sorry, don't have the notes anymore and I don't recall what the final velocity numbers were).

As I've been playing with my .223 Rems more, including a couple gas guns, I may have to work on recreating that load again...

Interesting, I am wondering if crimping removes run out? Or perhaps applies consistent neck tension? Maybe both?

This vid is a pretty good example of crimping.I like how he shoots round robin in a half assed kinda way.

 

[memilanuk]

Interesting, I am wondering if crimping removes run out? Or perhaps applies consistent neck tension? Maybe both?

I think it's more a matte of raising the starting pressure to where it changes the burn characteristics of the powder. If you play around in QuickLoad, for example, there is a default value for start pressure, with several suggested values depending on jumping, jammed, bullet construction (jacketed copper over lead, cast, monolithic solids, etc.), coating (moly), etc.

 

[Twitchy]

I attempted to years ago and gave up trying to chase the velocity. No idea what BH or LC used in the originals, but I can't replicate the velocity.

Oh and a vid of the 12 for giggles.

 

[Canuckenstein]

Video links are dead.

 

[nonnieselman]

Ive never tried to replicate the 262 velocity but i use H4895 with 77gr TMKs and they shoot very good at 600 yards. First 10 shot group was .9 MOA, 2nd 10 shot group was .57 MOA, 3rd 10 shot group was .85 MOA.
In my 20" 223 Wylde 8 twist i use Lapua brass, BR4 primers, 23.5gr H4895, 77gr Sierra TMK @ 2.260" loaded on a Dillon 550. I think the velocity is around 2775fps with the drop chart from 100 to 600 yards. I had to add a little more than the chart said to get out to 1000 but i think they were running out of steam and the wind was hurting me.

 

[Canuckenstein]

What do you think about lapua .223 brass? I’ve been told it can be scrappy(compared to their other calibers). If you were getting 2775 then you were faster than 262.

 

[JeffT]

I read somewhere, can't recall where, but Black Hills blends the powder to get the desired velocity.

 

[Dusty Stevens]

Never try to duplicate a factory load. Every one i know blends their powders.

 

[Dusty Stevens]

Not Mk262 per se, but years ago there was a BH 75 BTHP load that was really popular with Service Rifle shooters, very similar specs as Mk262. Everyone said 24-ish of TAC. I did a normal load workup, from 23 on up past 25 gn, and all I got was lousy accuracy and over gassed to the point of dang near ripping the rim off. Velocity was way low, and ES/SD were all over the place. Some where along the line, someone mentioned crimping to alter the burn characteristics of the powder. Like most people, I'd always heard - and repeated - that you never crimp 'match' ammo.

Finally I went to pull five bullets of the factory ammo just to see what was in there. One, it sure as heck looked like TAC. I know that isn't definitive by any stretch, but just sayin'... Two, it was right on 24.2-24.3 gn. Three, and this is where it gets interesting... those bullets were in there hard. I mean, I couldn't even *budge* them with a kinetic puller. Finally went out and bought a press-mounted collet-style bullet puller. Even with that, I had to cinch it down to the point where the bullets were physically deformed - in no way reusable - to get them out. If they weren't crimped in there, they were the next best thing to it.

So... I got an inexpensive Lee taper crimp die - I think they don't make that one any more, but supposedly their current 'factory crimp' die does an equivalent operation and set it up in the press so it was just barely touching the case mouth. I loaded a few like that, then turned it 1/2 turn, loaded some more, turned it, loaded some more, etc. etc. Not sure I ever got quite brave enough to get quite as tight as that factory ammo had been, but definitely way more than I ever would have normally gone. Certainly more than I think I could have reasonably achieved by just using smaller neck bushings and/or no expander, not without having major issues with seating the bullets.

The range session... was enlightening. You could literally see on target as the groups tightened up as the crimp increased. What had been a 3-4" load worked its way down to 1/2 moa or better, with the velocity coming up and tightening up at the same time (sorry, don't have the notes anymore and I don't recall what the final velocity numbers were).

As I've been playing with my .223 Rems more, including a couple gas guns, I may have to work on recreating that load again...

Bullets were welded in- dissimilar metals. Next time if you run them in deeper by a few thou in a seater die theyll come right out.

 

[cmillard]

I tried tac and had poor results. I switched to aa2520, and had much better results with greater accuracy.

 

[JAlfred]

Consider XBR 8208, velocity will get close and accuracy has been excellent.

I have burned 10's of pounds of TAC behind 68-77 gr bullets and still have plenty left but today I would reach for XBR.

With TAC, consider a little more neck tension and a hotter primer (CCI 450s or Rem 71/2). It can favor warm loads for best accuracy.

 

[r bose]

I'll add 3 things. Crimping of any cartridge requires exact as possible trimming from one case to the next. I too have had better accuracy crimping service rifle ammo. Next, I find any ball powder requires a hot /hard cup primer.........i.e. 7 1/2's and 450's. NO 400's, 6 1/2's or Winchesters for me.

Also, try alliant 2000-mr powder. I know several guys using it in XTC matches and the speeds, and accuracy are amazing. I have not switched yet (haven't ran out of loaded ammo) but have tested and I'll say this. Out of a 20" service rifle barrel, mag length ammo, a 77g Nosler at 2800 FPS in very obtainable. These are being shot at 200/300 yard lines in XTC matches. At 600 yards any 80-82g bullet shot single load (loaded long) 2825 FPS is where most are.

For these speeds you'll need to be in the 27ish grain powder charge. Alliant shows 25.2g as max for 223. 5.56 ammo is about 8k PSI higher so your powder charge increases. As always WORK UP YOUR LOAD. This powder is a bit temp sensitive as any ball powder so charge will depend on your conditions.

 

[Canuckenstein]

I'll add 3 things. Crimping of any cartridge requires exact as possible trimming from one case to the next. I too have had better accuracy crimping service rifle ammo. Next, I find any ball powder requires a hot /hard cup primer.........i.e. 7 1/2's and 450's. NO 400's, 6 1/2's or Winchesters for me.

Also, try alliant 2000-mr powder. I know several guys using it in XTC matches and the speeds, and accuracy are amazing. I have not switched yet (haven't ran out of loaded ammo) but have tested and I'll say this. Out of a 20" service rifle barrel, mag length ammo, a 77g Nosler at 2800 FPS in very obtainable. These are being shot at 200/300 yard lines in XTC matches. At 600 yards any 80-82g bullet shot single load (loaded long) 2825 FPS is where most are.

For these speeds you'll need to be in the 27ish grain powder charge. Alliant shows 25.2g as max for 223. 5.56 ammo is about 8k PSI higher so your powder charge increases. As always WORK UP YOUR LOAD. This powder is a bit temp sensitive as any ball powder so charge will depend on your conditions.

I am using the Lyman Ezee trim if the case(s) can’t be trimmed it gets culled to the plinking pile (or turned into 7.62x25)I try to eliminate as many variables as I can.

I made a torque wrench press handle for my press(cost me $17.00USD and was super easy).So I can measure crimping force in ft/lbs and remain consistent as possilble.

Off topic but I am going to be loading for my 8mm Mauser and will be trying this (torque wrench and Lee collet)out for neck sizing. I don’t think it will have any effect on neck tension. But we shall see.

ADI has a great powder comparison chart. I have never seen their powders in Canuckastan though. My girlfriend/wife owns a gun store and I have been to many many different dealer events. Even alliant powders can be hard to come by.