Does anyone have any experience with this new powder in a compressed state? It is a ball powder and I found that using the data from the Alliant website in the 338 Federal, the loads are highly compressed.

I am loading 210g Barnes TTSX and 210g Partitions for an upcoming trip to RSA and the 338 Federal is the primary rifle. I don't usually use ball powders due the the supposed problems of compression and temperature but this powder gives the 338 an extra 200 fps so it is worth investigating.

I've called Alliant several times now over the past few weeks and left messages but I can't seem to get anyone to call me back. To add insult in injury, so to speak, when I chronographed the loads the best velocity I could get using a max loading, was still 175 fps less than what Alliant claims as max velocity and that was pretty compressed, too.

Does anyone have any suggestions? Plan B is to simply use the max loading and forget the extra 175 fps. That is too bad too, as it would have the same trajectory as my 30-06 - 180g.

Thanks,

I just knew if I posted this question I would immediately get a call from Alliant. I did, about an hour later.

They suggested I increase my powder 0.5g at a time and chrono the results. I will do that tomorrow and post the results.

However, I did load up the rounds today and man, they are definitely compressed in a big way. The powder is 3/4 of the way up the neck and the bullets compress it back to the start of the shoulder! But, they did load ok so we will see what happens tomorrow.

Robert, I'm compressed ballpowder to the point where I had to back off because I was bulging the cases. Funny thing is, these are some of my best shooting loads.

Regarding your velocity, remember, primers, case, and barrel length can all effect velocity as well.

That powder being designed for a longer, taller average,
pressure curve, needs barrels about 28-30 inches long
to get that extra advertised speed, in 30-06 size cases.
But everybody with the uzi barrel syndrome(UBS)
wants short barrels.Factory test is 30".........ED

I would load them and remeasure OAL in a week. Too much compression wreaks havoc with the OAL. Maybe not immediately, but over time it can be a problem.

I'm just starting to test the 2000MR and 4000MR powders. I have some loads for my .280 to try hopefully later today.
My advice is make accuracy your main concern and not worry about velocity. If your 06 is more accurate and flatter shooting than the .338 then it would be a better choice for PG. I've seen a 7mm-08 out perform a .338 mag in Namibia as it put the bullets in the kill zone more often than the .338
Just my .02 cents worth.

small trick i learned -0 after you charge the case, start up your case vibrator/polisher. hold your finger on top of the case & touch it to the top of the vibrator for a second or 2. it will really settle the powder

Thanks for the tips! I will remeasure the length again today to see if anything changed. Also, I'll put a round in the bottom of the magazine and see if recoil has any effect on the length as well.

I also plan on saving 24 rounds and chrono-ing 3 once a year to see if compression and time has any effect on velocity as well.

Fortunately, my trip to RSA is only three weeks away so if time has any effect on this, it should be minimal.

BTW, the test barrel for the pressure loads at Alliant was the same - 24 inches. I think this is one of the few times a test barrel is the same as my rifle!

quote:

Originally posted by Antelope Sniper:
Robert, I'm compressed ballpowder to the point where I had to back off because I was bulging the cases.

I had that happen when I insisted on trying QuickLoads suggestion for a max load of Norma MRP in the 8x64S case. There is definitely a point where a lot of compression becomes too much compression...

- mike

quote:

Originally posted by RobertD:
I will remeasure the length again today to see if anything changed. ..

If you measure the Overall Cartridge Length from the Tip of the Bullet to the Case Head, you will always see a variation. That is caused by different lenghts of the individual Bullets.

The only reason I mention this is to prevent you from thinking you have a problem when you might not.

When measuring Cartridge Lengths, you will get more reliable information from the Ogive to Case Head. If you do not have a Hex Comparitor(which is a waste of money), use the Largest Socket from your Tool Box which will not slip past the Ogive and measure from the Top of the Socket to the Case Head. There will still be some minor variation, but not nearly as much as measuring from the Bullet Tip.

Of course, you really needed to do this in the beginning so you could compare the results.

Best of luck to you.

I used to get freaked out about compressed loads until I started loading for the 458 Lott. Seems like you crimp more to keep the bullet from popping out because of compression than for recoil considerations.

I have a Stoney Point comparator to measure case length. And, I noticed today, they are moving forward. The Barnes bullet has moved forward enough that it no longer fits in the magazine.

I did find a nice Partition loading at 53.5g of MR2000 at 2643 fps. But the Barnes TTSX I am going to stick with the 52.7g of MR2000 at 2625 fps.

I never did get to the advertised 2750 fps but this is what my rifle can do accurately.

I thought I would buy a Lee Factory Crimp die and redo these loads with a decent crimp on the case and see what happens.

But it won't happen in time for Africa this trip.

If I was in your shoes and planning to use those cartridges on an expensive hunting trip to Africa, I'd use a different powder.

For a hunt of the type which costs significant money, I'd want reliability every time over velocity. That .338 isn't designed as a high velocity cartridge anyway.

So, just as a possibility, I'd consider a powder which burned a bit faster, bulked a bit lower, and didn't require ANY compression to work uniformly and reliably.

Alberta, That is a good plan. I do have a back up rifle, 30-06 using a load that I have lots of experience with. I ended up reducing the loads and sticking with the lower velocity. I did find a sweet spot there and I also have some factory ammo that works pretty well, although the bullet weight is a bit low.

"Highly compressed " , isn't that the reason that early factory loads of the 458 Win had reliability problems ?
Go for reliability and accuracy , and forget about the rest.

Yes, but I forgot which powder caused the problems.

I did check with the factory on compression and they did say it was "normal", so I guess they know what they are talking about.