Black Hills 77gn 5.56 ammunition

[ukrifleman]

Hello all,
I have had an enquiry from a shooting buddy in the USA, about Black Hills 5.56 77gn ammunition.
He wants to duplicate the round and has heard that the powder used although unknown, is probably of European manufacture.
Does anyone have information on this round and more specifically, what powder is used?

ukrifleman.

[DaveB]

The round is marketed to civilians under a generic name, but is more commonly known as "Cartridge 5.56 mm Special Ball Long Range Mk 262 Mod 1".

As I recall the propellant is AR 2206 .2 - an Australian-made military propellant, which is neutral-burning due to it's proprietary slotted-tube geometry. It is also very temperature insensitive. I will check my notes on this, and confirm later on.

Some AR-series propellants are available under other names from Hodgdon. They buy a lot of Australian propellants and re-mark them as their own. Normal AR2206 is available from Hodgdon as BLC(2) for example. Exactly what the difference between the commercially available propellant, and the version in the Mk 262 I do not know.

[Laurie]

Some AR-series propellants are available under other names from Hodgdon. They buy a lot of Australian propellants and re-mark them as their own. Normal AR2206 is available from Hodgdon as BLC(2) for example. Exactly what the difference between the commercially available propellant, and the version in the Mk 262 I do not know.

H. BL-C(2) is a US made ball propellant originally developed by Winchester Western during WW2. Bruce Hodgdon bought hundreds of thousands of .303 Mk7z rounds manufactured by Winchester for the UK under lend-lease arrangements and which became surplus when the war finished. They were demilled and the powder bagged and sold. This was Ball Lot C-1. When it had all gone, a demand remained for the powder and Hodgdon went back to Winchester / Olin Corp and asked if they could make more - a suitable replacement was produced and to differentiate it from the wartime version, it became Lot-C2, hence the name. It is made these days by General Dynamics, St Marks in Florida.

[DaveB]

I should have learned by now, never rely upon one's memory especially first thing in the morning after a night of little sleep. I hardly know where to start. https://www.full-bore.co.uk/posting.php ... p=344613#I would delete my earlier post entirely to spare myself embarrassment, but for some reason it won't let me.

Let's start with the propellant in the Mk 262 Mod 1 is not AR2206 v2- that related to a completely different round (F1A1). The propellant in the Mk 262 is Ramshot a smokeless double-based propellant in spherical form.

Then as noted above BL-C(2) is not 2206 made in Australia, rather it is roughly equivalent to 2206.

Sorry folks. I will endeavour to engage brain properly and check my notes before keyboard next time.

[Laurie]

Interesting that it is a Ramshot powder which ties in with the Mk 262 allegedly using a European made propellant. (Most Ramshot powders are manufactured by PB Clermont in Belgium and the company is a world leader in making military-friendly smallarms ball-type powders overcoming most of the genre's disadvantages such as being dirty burning and temperature sensitive.)

Whilst there is often a superficial attraction to trying to duplicate a factory ammunition loading exactly, (and difficulty too as bulk powder lots are used that likely don't match canister grades exactly, or sometimes even barely approximately), having tried umpteen powder combinations with various 77s in 223 in a straight-pull AR-15 some years ago, I found it one of the easiest combinations around to get outstanding results. Half a dozen powders gave really good groups, Hodgdon H4895 just shading the others maybe.

[ukrifleman]

Many thanks to all for your input.
I will make sure the information is passed on.
ukrifleman

[safetyfirst]

Interestingly my straight pull 5.56 shot best with 22.5gn of ram shot ram tac behind a 77gn sierra match king.

[Andy RV]

I'm surprised that it's not loaded with St. Marks Powder however this (old) presentation confirms it;

http://www.dtic.mil/ndia/2006/smallarms/faintich.pdf

That leaves PBC (Ramshot) or Thales.

[DaveB]

It's Ramshot. I got that straight from Jeff Hoffman - President of Black Hills.

[ukrifleman]

It's Ramshot. I got that straight from Jeff Hoffman - President of Black Hills.

Thanks for that Dave.

I assume we are talking about TAC?

I don't suppose you can put the cherry on the cake and confirm which powder AND the charge!!