Thread: 338 ARC - An Early Guess At Reloading Data

11.5" barrel, 160gr TTSX, max prescribed load of CFE BLK, giving 1940fps.

I have a heap of Barnes .338 160 TTSX projectiles availible for sale

Me too

Not bad Pommy, whats ya OAL ? looks on the shortish side ...

Hodgdon say 2.200", I went with 2.215".

Max (26.8gr) is only meant to be 41700psi. Looks like that's mainly because you run out of case capacity and are compressing the powder. I think seating them out closer to 2.3 (assuming the throat allows) might make enough space for enough extra powder to get up over 2000fps comfortably.

ph call from my local gunshop this arvo, my back ordered 338 ARC & 22 ARC brass has showed up.

I'll probably leave the 22 ARC build til mid next year (most likely just a Stainless Howa mini 223 20inch varmint with a Arc reamer run up it)

The TTSX hit the rifling at 2.310" so I seated them out to 2.260" and went up to 28gr of CFEBLK. Didn't get a chance to chrono - probably doing somewhere around 2050fps - but I did shoot a few roos...

Wasn't expecting miracles, as they are hard bullets that need to be driven fast for good terminal effect. This proved to be the case with a few running from hits where a 223 would have flattened them. Bullets did do something though and would penetrate for miles and put down a deer no problem at short range.

Originally Posted by Pommy

The TTSX hit the rifling at 2.310" so I seated them out to 2.260" and went up to 28gr of CFEBLK. Didn't get a chance to chrono - probably doing somewhere around 2050fps - but I did shoot a few roos...

Wasn't expecting miracles, as they are hard bullets that need to be driven fast for good terminal effect. This proved to be the case with a few running from hits where a 223 would have flattened them. Bullets did do something though and would penetrate for miles and put down a deer no problem at short range.

This seems to be a similar story to the 300blk. Most of the supersonic projectiles were too strong for the velocities, so things like varmint bullets became the go-to. I'm not aware of any very light construction .338 projectiles yet.

Sounds like powder coated very soft cast might be worth exploring...

Hey Pommy I reckon your probably too low on the expansion window for a swagged TTSX, I'll be ordering some 161gr OEP at the end of the month so I can do some reloading, night have to send you a sample pack for testing

No doubt it's very close to the minimum expansion threshold. I had a look at one that I recovered that was shot at 50m. The bullet hadn't exactly pencilled through... but the wound channel was pretty minimal.

Happy to give OEP's a go. As and when Makers come in then I'll have some 165gr ones of those to play with too.

Email podcast@hornady.com and let's lobby them to do a 150-165gr V-Max / ELD-VT.

Finally ordered some 2 boxes of the 338 Cal 161gr OEP's, not a long projectile at just over 30mm. Not trusting Quickloads data for a new cartridge, I grabbed out some powders to see if there were any discrepancies.

Seating these 30mm long projectiles about 7mm deep into the case neck for a rough COAL of 56mm or 2.200, I suspect I'll be able to seat out further with the Howa mini mag length but I'll go on the short side for the time being.

These approx powder charges were measured with the calipers and should reflect about 100% case fill. I'll also test N110 later but its very similar to 2205 in volume and burn rate.

338 ARC 1.300 inch Hornady brass COAL 2.200

2207 23.0-23.5gn Actually QL was pretty close here

2205 24.0-24.5gn QL suggested 22.6 gn would be 100% charge weight

Power Pro 300MP 26.5-27.0gn I dont have QL data for this powder so I wont speculate but generally 300MP performs as good a Lil Gun or better.

Reamer should be here in a few weeks, whilst another month or so for the barrel.

@billlo, could you please run quick load with Reloader 7 and see what it says with same projectiles weight? Also, would these powders any good for sub load with 280/ 300 gr projectiles?
Thanks

The 165 ECX go well out of my 8.6 blackout
Get good mushroom out of them
I am running a 1-1” twist 18” barrel
Rem ti long action
And getting pretty easy 2350 fps
Accurate 1680 powder fed mag primer
Have found that moly coating allows
Me to drive them harder with less fouling
Or pressure

Originally Posted by Friwi

@billlo, could you please run quick load with Reloader 7 and see what it says with same projectiles weight? Also, would these powders any good for sub load with 280/ 300 gr projectiles?
Thanks

Hey Friwi I get a mate to do my QL data, Ill see if he can bang out the numbers. It appears the finer fast pistol powder are doing the goods with the Sub loads from my research, what can you get ?

I think Lil gun, 296, H110, N110, PP300MP, CLK BLK will all do the Subsonic stuff well.