Hi Jeff,

My interest in this new bullet is for highpower service rifle competition.  Can you provide any insight on whether Sierra will add such a tip to their .224 80 grain Matchkings?  Sierra 77's seem to dominate 200 and 300 yard service rifle competition but the new published BC for the tipped version now equals that of their 80 grain bullet, the top 600 yard competition bullet.  It begs the question of what kind of BC could be achieved with a tipped 80 grainer.

Thanks!

This will be an awesome coyote load!






.

Rjexcellent,
I know of no plans for Sierra to add a tip to the 80s. One probably problem is it may make the already long 80 grain bullet to long to stabilize in a 1/7 twist. I am sure Sierra would be happy to discus this with you. Another question from their perspective would be how much demand would there be.Jeff Hoffman

Jeff,

Is this ammo available anywhere in SD? Can i just swing past your factory and pick some up the next I'm in the hills? :)

Where will be the best places to get this stuff when it comes out?

gbisch and KCode98,

If you call our office and provide your zip code we can advise closest dealer to you, or set you up with a dealer that can ship to you. 800 568 6625.
Thanks, Jeff Hoffman, Black Hills Ammunition

Buster Beaver has them in Wilsonville, Oregon (near Portland).

Any word on price per 50 rd box?

Does anyone have the G7 ballistic coefficient for the tipper 77 grain?

The 77 SMK is only .190 and a G1 of .362 (I think).  So .420 G1 is out of the ballpark.

You've got the numbers right.  It's a huge increase.

Can anyone tell me how much these are going for per 50 rd box?

I beg to differ with you kind sir. 3 round group, Black Hills 52 grn V-mav... I was using a 20 rnd GI mag..

A. AMAX. The 75.

LMAO, went for the kill shot, and Combat Jack was not there.  I don't think 52 gr. Vmax's have anything to do with the conversation.  People are making a comparison to the 75 AMAX, with the new SMK tipped.  Nice group though.

Sweet.

I went back and 2x checked. I am still missing the post were it states the 72gr AMAX prior to my pic post.

The only experience in 556 I have with amax is what I posted. As I'm trying to find what my Bushy likes shooting the best. Thus to date its the AMax... However, I do believe I will be calling my LGS Monday AM to order a box of BH 556 SMK..

As to the group, thanks. I can't complain as its a stock Bushy varmiter with a Young NM BCG.

Jeff,
Does Black Hills have any plans to release a .223 loading of the TMK?

Ahhh, gotchya.. Tnxs..

gwood188,

No plans at this time. Jeff Hoffman, Black Hills Ammunition

No, there's a 53gr. A-Max as well.  About the only difference in construction (I believe) between it and the V-Max is a boat-tail.

FYI... I just spoke with Buster Beaver... and they only have the "Regular" Blackhills 77gr OTM.... No TMK.

I called my dealer.. They made some calls about and it looks like I knew more about the rounds/when it was hitting the market then they did..

I gave them my contact info and told them it should be hitting the shelves in a week or so.

TLDR= LGS knew nothing can't order any..

These guys say they have 77gr TMK in stock.

I have been a long time follower of ar15.com, and just recently created an account, so this is my first official post. I recently ordered a 500 round case of the TMKs from OldVirginia (who currently has in stock with I believe 1000 more cases inbound within the next couple of weeks) and am awaiting their arrival for reliability testing. My ARs in the past have had numerous failure to feed issues with BT and the tip breaking off on the feed ramps both with the Hornady VMax and Nosler BT. Has anyone else encountered the aforementioned issue? If so, any idea why this occurs? My AR10 deforms the nose a bit on the Nosler Accubonds and Hornady AMax, but never breaks them off.

This probably belongs in the Tech Forums.  That said, it sounds like your feed ramps are possibly too steep or too rough.  Why not have a gunsmith take a look

Found this seller on Gunbroker, with a link to his own site.  Has a short, but positive amount of time on GB,and prices seem great on his regular site.  A lot better than the $750 someone on the EE here is trying to get for a case of 500.


https://www.thefinalimage.com/ammunition/rifle/223-5-56mm/

Been looking forward to this 5.56MM 77gr. TMK loading ever since it was announced. All I have seen up until now were a few cases of SECONDS. DOD/military rifle teams probably got the earlier lots (as they should). The TMK ammunition received is headstamped WCC 13 (+). The mil-spec brass shows red lacquer sealer on both the crimped primer and the crimped 77gr. TMK bullet with cannelure. But only the primer is actually sealed (Thanks Carl!). This mag-length 77gr. TMK load has the same G1 BC of 0.420 as the over-mag-length 80gr. SMK load many shooters use at 500yds. and beyond. Very nice looking ammo.

BHA 77gr. SMK OTM based MK 262 MOD 1 over BHA 5.56mm TMK: Fired from my 18" barrel, the TMK load should have just about 5 feet less drop at 1000yds. than the 77gr. SMK OTM based BHA MK 262 MOD 1 load. The TMK load is a game changer where mag-length ammunition is required. Looking forward to testing/using it.



With a COAL of approx. 2.248",  the BHA 5.56mm 77GR. SIERRA TMK cartridge is clearly magazine length. The 1.070" 77GR. SIERRA TMK bullet is slightly longer than the 0.996" 77GR. SMK OTM bullet w/c used in the BHA MK 262 MOD 1 AA53 cartridge. And the TMK cartridge contains a spherical propellant.




EDIT:

77GR. TMK BC DATA from SIERRA's Website: This bullet requires a barrel twist rate of 1x8” or faster.

Ballistic Coefficients and Velocity Ranges

.420 @ 2400 fps and above
.415 between 2400 and 2000 fps
.395 between 2000 and 1750 fps (I used .395 BC for 1900 FPS straight across the board for expansion/fragmentation distance calculations.)
.380 @ 1750 fps and below

BHA 5.56MM 77GR. fired at 80F/300FT. MSL/29.92" with M4 suppressor: Subtract 30 FPS/15 yds. for non-suppressed use. 1 FPS/ 1 Degree F is a ball park Thermal Variation figure (0F to 135F) for the BHA 5.56MM 77GR. TMK load.

Barrel Length: MV@12FT./ Distance 77GR. TMK slows to minimum expansion/fragmentation velocity of 1900 FPS using .395 BC

18" SS Krieger/CLE: 2784 FPS/ 437 yds.
16" Colt M4:--------- 2705 FPS/ 403 yds. (new 6940 barrel)
14.5" Colt M4A1:---- 2602 FPS/ 355 yds. (well used barrel)
10.0" Colt M4:------- 2344 FPS/ 232 yds

The 77GR. TMK@1906 FPS was a tailored handload but the other (2) shots were factory BHA in 10.0" & 18" barrels.


Business End of the Non-Yaw Dependent/Expanding/Fragmenting 77GR. TMK VS the Yaw-Dependent/Non-Expanding/Fragmenting 77GR. SMK OTM based MK 262 MOD 1: The TMK acetal resin tip is there to help achieve the high BC. On impact with a flesh & bone target, the tip is forced back into the large hollow point allowing the TMK bullet to expand  hydraulically. According to Sierra, the TMK jacket is heavier than the jacket used on their explosive-expansion Blitz varmint bullets so TMK expansion is more controlled. IMO, we still need to get a better idea of the TMK's level of controlled expansion. Sierra will only recommend their TMK/SMK bullets for use on varmints. Given the number of enemy that have been felled with SMK OTM based DOD cartridges such as MK 262 MOD 1/M852/M118LR/MK 316 MOD 0, I don't think there is much doubt that SMK bullets can been used effectively on flesh & bone targets quite a bit larger than varmints. And so far, TMK bullets appear to be even more effective on flesh & bone targets than SMKs.

I'll have to pick up a box of these to try out. Jeff you know how well these work out of a 10.5?

Is that sealant on the case mouth on a .mil or .civ round? Can you confirm/deny that the civilian stuff we will get will be sealed?

12_gauge,
      I looked at the first row of (5) cartridges with a magnifying glass. All (5) definitely show red lacquer on the case mouth. Boxes are ink stamped "1806182604".

EDIT: Only the primer is actually sealed (Thanks Carl!)

Here is a MACRO of a handful:

Seen. Nice!

Civ round is sealed as well!

Now, if this bullet were bonded...*dreaming*

LEID,

Thanks for measuring bullets and great photos!

that is a long bullet.  A bit longer than a 70 grain TSX.  (1.036).

Does anyone know if it will stabilize in a 1:8 and if so if BC or accuracy suffers?

I hate to tell you folks this,but the case mouths are not sealed on this ammunition. The red you're seeing in that area is more than likely a very light smear of primer sealant that ended up in that area while the brass was being produced at Winchester. The primers are sealed of course. Thanks, Carl

Thanks for the truth in advertising. Impressive!

Thanks Carl. We do appreciate you & Jeff keeping us straight on the facts.

Morning Carl/Jeff,
    A question popped up that I just do not have accurate information on. So I had best get it straight from the "horse's mouth" so I don't resemble the other end. What is the valid range of velocity for the .420 BC on the 5.56MM 77gr. Sierra TMK loading? Am putting together a "first look" data card out to 1000yds. for the TMK cartridge. Initially, data card will be based on the MV at 12 Ft. of 2825 FPS (5 shot average/300 FT. MSL/95F/29.92) chrono'd with BHA 5.56MM MK 262 MOD 1 in the 18" 1x7.7 SS Krieger/ CLE 5.56MM chamber barrel with M4 suppressor that will be used. Will get actual chrono numbers on the 5.56MM TMK cartridge at that time & at then-current ambient temperature which I sure hope will be much cooler than 95F. No hurry, plenty of time left to get it done before my next shoot. And no worries, I have a basic shooter's understanding of thermal stability of the common types of .223/5.56MM propellants as it relates to expected MV at a given propellant temp.

                                                                                                                                                              TIA!

EDIT: 77GR. TMK Data from Sierra (below):

"This bullet requires a barrel twist rate of 1x8” or faster."

0.224"/ 77GR./.219 SD

Ballistic Coefficients and Velocity Ranges
.420 @ 2400 fps and above
.415 between 2400 and 2000 fps
.395 between 2000 and 1750 fps
.380 @ 1750 fps and below

LEID,

I plugged in your data to the JBM calculator and you should get 34.5 MOA come ups at 1000 and cross the 1000 yard line at 1215 fps, so better shoot on a hot day!

My Black Hills 175 grain SMK's need 36 MOA at 2620 fps.  This works in real world at 3200 feet asl.

I cant believe that Sierra would not have a G7 rather than a G1 for this bullet.  Though I use a G1 of .490 for my SMK (rather than .505) because thats the average of G1 BC's within its velocity range and it is really close.  

2750 fps gives you 1183 fps at 1000 yds with speed of sound 1154 at 300 feet asl.  

36.7 MOA, big difference in come ups for 75 fps.  

Let us know how it goes!

Is it the general consensus that this round is better suited as a hunting round than as a tactical round?

No.

Thanks 380 guy. Just need Carl/Jeff to supply valid velocity range for the .420 BC on the 77gr. Sierra TMK bullet. Valid velocity range for the .362 BC on the 77gr. SMK OTM w/c bullet as used in the MK 262 MOD 1 cartridge is 1700-3000 FPS. Below 1700 FPS, it drops to .343 and above 3000 FPS it goes up to .372. All BCs above are G1. Best thermal stability variation number I have on the BHA MK 262 MOD 1 cartridge produced after 2005 lot 96 (BLH05L096-001) is basically 1 FPS/degree F for small temp. changes. For full Texas summer heat to full winter temperature changes, I use 1.15 FPS/degree F (-10F to +135F). The nitroglycerin (NG) in double based propellant appears to not add much if any MV over single based propellant right around 0F. One of the hardest things for me to do is to get new 5.56MM loads on paper past 500yds. Once on paper, it's just a math exercise. If I can get the numbers about right before the shoot, it will cut down on going back and forth checking targets. Trigger-pull conditions preferred for initial testing usually don't last long. Much prefer to practice shooting steel but I need solid numbers first. Also need to pick out a scope rail for shooting past 750yds: EGW has a nice aluminum 20 MOA Picatinny AR15 rail but there might be others. Wish Leupold made one for the AR but I don't see it. Thoughts?

I enjoy shooting for accuracy but the BHA 5.56MM Sierra TMK load also has a date with a 10" LWT M4 I have used for years. Would also like to test the BHA 5.56MM 62gr. TSX load in the 10" but my dance card is getting pretty booked.

Edit: I do have the BHA .223 pressure 62gr. TSX loading to test but not the 5.56MM yet. Will get quick MV numbers on 10"/14.5/16"/18" and shoot a couple quick groups with it.

 




 

I started using the BHA MK 262 MOD 1 SECONDS around 2006 for game control/personal hunting and been using it ever since: deer/beavers/etc. Killed 100s. Accuracy was better than any factory cartridge I had previously used especially in an accurized rifle.  And even out the 10" M4 I use as a truck gun, it was lethal. You just have to place your shot correctly but the accuracy advantage made that easy. Longer barrels just made it more lethal.

Any word on Sierra selling the bullets to the public?

Would like to get some and try them out in my hand loads.

LEID,

I dont know if you are going to need a 20 MOA rail for this bullet?

If you can get sighted in anywhere near center of scope your come ups appear to be similar or better than a 175 SMK with a .308 winchester.  

You should only need a 65-70 MOA adjustable scope to get on qt 1000 yards.  (1/2 of that is about your elevation).

A 2.5 x 10 NF or most of the Luepold Mk4's should get you there.  

I did not know they were available for a flat top.  Cool if they are.  Opens up more scope choices for sure.

380guy,
    Long ago, the BR guys I shot against taught me that the best/most accurate optics in any given scope are towards the middle of the adjustments. For punching paper & shooting steel at LR, 20 MOA rails are now about standard with EGW (Evolution Gun Works) rails having a very good reputation.