LOAD DATA HELP: Sierra MatchKing Boat Tail Hollow Point 30 Cal 168 Grain #2200

[usabaker]

How fast do you want to go?

It would be above 2600 FPS Sierra has rated their matching BTHP at .462 @ 2600 fps and above. I'll be developing hunting rounds on Hornady 165gr GMX haven't set in on a powder yet, but might just load RL-17 since a have a pound of it already and try the IMR4064 to see what works best.

[CINDERS]

If your trying to get a max burn the ADI AR2208 (IMR 4064 equivalent) may be a bit slow, your better off using a faster powder like AR 2206H I use in my APRS(Ace Precision Rifle Systems in Australia) .308 Remington custom build which has a 25" Kreiger match grade barrel I have had the rifle for a fair while and have not changed the load data supplied by the factory it came from.
I use 168gn Hornady A-Max due to this projectiles devastating wound capabilities accounting for a fair few foxes out to 400M have found out to their peril, I use Lapua brass, uniform the primer pockets, anneal the case necks with an AMP machine and use BR2 primers behind 42 grains of AR2206H.
Another powder to use is AR8208 its also faster than 2208 (My wife reloads this powder for her Barnards behind 155.5gn Berger VLD's) it is a fine granule not a ball powder and meters really well from thrower and electric dispenser.

Anyway to prove the load works I've enclosed a few targets shot off a bench with a bi-pod no rear bag @100M 25 months apart the flyer is me, but shows what the load and rifle are capable of the one at .3 MOA this rifle can maintain all the time the only limiting factor is me.
As always though with all reloads start 10% under and work up I am not responsible for use of this data by anyone.

[Sunray]

"...in a 22" barrel..." That'd pretty much be any load. 22" is the original barrel length for the .308. Smokeless isn't dependent on barrel length for it burning.
The twist won't change the velocity much if at all. The twist is about stabilizing the bullet. A 1 in 10 will do that as well as a 1 in 12. SA Inc "Loaded" M1A's have 1 in 11.
Hodgdon's site data was tested with a 1 in 12(Standard M-14 twist), 24" barrel.

[usabaker]

Smokeless isn't dependent on barrel length for it burning

It was about optimizing the gases. Depending on the rate of burn, too fast can cause pressure jumps and too slow and bullet will exit the barrel without fulling burning the powder. You can experience the later using IMR 4350, it was great until you got close to capacity in the casing then you were just spewing powder out of the muzzle. Does make nice night pyrotechnics.

[Parashooter]

Perhaps counter-intuitively, we actually see a higher proportion of powder burn as the charge, pressure, and temperature increase. Put simply, with lighter loads of slow powder, it never gets hot enough to burn well.

QuickLOAD output gives an idea of the dynamic involved. (Focus on "Burnt %" column)

Cartridge : .308 Win.
Bullet : .308, 168, Hornady BTHP Natl M 30501
Cartridge O.A.L. L6: 2.800 inch or 71.12 mm
Barrel Length : 22.0 inch or 558.8 mm
Powder : IMR 4350

Predicted data by increasing and decreasing the given charge,
incremented in steps of 2.381% of nominal charge.
CAUTION: Figures exceed maximum and minimum recommended loads !

Step Fill. Chg Vel. Enrgy Pmax Pmuz Burnt B_Time
% --- % - Grns fps ft.lbs psi - psi - % -- ms

-23.8 75 32.00 1697 1075 17455 4541 65.9 1.832
-21.4 77 33.00 1748 1140 18650 4777 67.5 1.781
-19.0 80 34.00 1800 1208 19931 5016 69.1 1.731
-16.7 82 35.00 1852 1279 21302 5257 70.7 1.683
-14.3 85 36.00 1905 1354 22770 5500 72.3 1.636
-11.9 87 37.00 1959 1431 24334 5744 73.8 1.591
-09.5 89 38.00 2013 1511 26032 5989 75.4 1.546
-07.1 92 39.00 2068 1595 27845 6234 76.9 1.503
-04.8 94 40.00 2123 1681 29789 6478 78.4 1.461
-02.4 96 41.00 2179 1771 31880 6721 79.9 1.419
+00.0 99 42.00 2236 1864 34128 6962 81.3 1.379
+02.4 101 43.00 2293 1961 36548 7199 82.8 1.340

[CINDERS]

IMR 4350 is your equivalent to our AR 2209 and thats a fairly slow powder, I don't have my quickload program installed at present as comp crashed but will reload it soon and do the calcs for IMR 4895 from the top of my head for the load I am using AR2206H think I am at about 98% burn the load Para's put up your throwing allot of gravel out the muzzle in unburnt powder I would not use AR 2209 (IMR4350 H4350 H414) in my 308 its too slow.

[usabaker]

QuickLOAD output gives an idea of the dynamic involved. (Focus on "Burnt %" column)

This is awesome data! You are right "counter-intuitively" until seeing this data I never really looked at it from this aspect. Interesting indeed. I have never heard of QuickLOAD; just looked it up I guess if I were a percision shooter this software would be invaluable But $155.00 is a lot of game meat.

Thank you for the information and a new way of looking at loads.

[usabaker]

I would not use AR 2209 (IMR4350 H4350 H414) in my 308 its too slow.

Hi Cinders, I stopped using IMR 4350 back in the early 90's because of the powder waste I was noticing from my muzzle and my conversion from LEE to RCBS. I started using it because back in the 80's that's what LEE was recommending and providing load data for.

For my new loads (for my son's rifle that I started this tread on) I have purchased from the input I have from y'all on this forum and reading I've done on non-lead elsewhere:

Hodgdon H4895
IMR 4064

Barnes LRX .308 175Gr Boattail bullets (For Hunting Only)
Hornady .308 Cal. 165 GMX Bullets (For Hunting Only)
Sierra MatchKing BTHP 30 Cal 168 Grain (Target and Testing the Rifle)

I'm going to run up a number of loads to see what his rifle likes best

Thanks for the help again

Bill

[CINDERS]

I think we will all agree there is no shortage of honest help in this site as its poor form to let some one struggle when we have been down that road and found the solution/s.

I will say that my AMP annealing unit I use is the way of things as brass does get work and fire hardened and this machine has made all the difference to obtaining consistent neck tension, I anneal every firing now on all my calibers

[usabaker]

I think we will all agree there is no shortage of honest help in this site ... AMP annealing unit

That's what I love about this forum and the people in it. Even if the topic is not strictly MILSURP every one is willing to give help and advice. I have yet to be flamed on this forum for asking questions that others might feel mundane. I am truly thankful for all of you here.

The AMP is way outside what I can afford. I've actually started on an annealing machine build. I went to the 2nd hand store and bought a used Canon laser printer. I just got done breaking it down and pulling out all the goodies I will need to build my machine. The printer has the DC motors, control circuits, power supply, gears, and shafts I needed. I'm working the electronics right now to figure out what is what on the boards. I was pleased to find a lot of sensors that I can make use of if I can figure out the control circuits and by-pass the microprocessor, ROM, and some of the control modules. If not I'll have to build three simple timing circuits to connect to the DC motors.

The first step will just be a simple shaft that rotates and indexes with the proper timing. Once I get that down I can work on making a continuous feed version.

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