.338 R.U.M. fans - Page 9

RUMLUVER · #**121** 08-08-2006, 11:03 AM

Sounds good Roy can't wait to hear the results!

royinidaho · #**122** 08-08-2006, 10:43 PM

Fired some loads for velocity and pressure checks.

Put 96 gr of Ramshot Magnum behind the Hornady 225 SP Interlock for a measley 2822 fps. That Ramshot burns like coal. I may have to reopen the old "One Time Coal Co." in Butler Co. PA and collect the bugdust for rifle powder.

89gr of RL-22 behind the same bullet produced 3068 FPS and may have been just a titch hot.

92gr of 7828 behind the same bullet gave 3094 w/no pressure signs

87gr 7828 behind the 250gr SMK produced 2877 and
88gr of 7828 and the SMK produced 2891

None of the loads were pushing any limits even for a 92 degree day.

Tomorrow I'll give her a cleaning and install the RSI strain gage and see how that gizmo functions.

ALl of the above loads were fired with a 1/8" flash tube installed. The whole idea of this testing is to see what kind of differences frontal ignition makes, if any. The RUM is a much better cartridge for this test than was the Win Mag.

RUMLUVER · #**123** 08-09-2006, 01:45 PM

Roy,

I also shoot 92gr of 7828 with the 225 Hornady Interlock and I'm getting 3151fps and with the 250gr Interlock I'm using 90gr of 7828 and getting 2998 fps with that load. As far as the RamShot powder I never had any luck with that either. RL 22 and RL25 have yielded good results for me with the 210 and 225gr TSX's from Barnes. Also I'm almost done with with my .264 WM I just ordered my stock yesterday it was a Holland fiberglass stock and it will be here in 10 days and then the work will begin for me. I can't wait this rifle project has been haunting my dreams for months now!

royinidaho · #**124** 08-11-2006, 10:42 PM

Here are the results of today.

With IMR 7858 and H1000 velocities and pressures are almost identical to the IMR reloading data. Never had that occur before.

92gr IMR-7828 and Hornady 225 Spire Point seated to a length of 3.016" from base to ogive (the crimp ring is a full 1/8" out of the case mouth. All shots with Flash Tube.

Don't worry about the group size. The bedding has some problems.

Here's the full skinny:

RUMLUVER · #**125** 08-12-2006, 12:58 PM

Intresting results it's always nice to see what others are getting for performance with similar loads. I don't have equiptment for obtaining pressure data but I do have a chrony so it was nice to see pressure data for that load. Thanks for posting and that and keep the results coming. By the way do have any plans on loading the 250gr TSX from Barnes?

royinidaho · #**126** 08-12-2006, 03:08 PM

By the way do have any plans on loading the 250gr TSX from Barnes?

Don't know yet. I'll go through some Sierra 250s some SMKs and 252 and 275 Wildcats before I get to the Barnes.....

Getting the correct bullet/powder combination for maximum accuracy and performance is going to be a task.....But fun.

RUMLUVER · #**127** 08-12-2006, 05:26 PM

Roy have you ever used any of the Swift A-frame bullets before? The make a 275gr slug in .338 and that would be a crusher of a round in the .338 RUM don't you think! I was curious as to how accurate those A-frames were but I havn't come across anyone who has used them before.

royinidaho · #**128** 08-12-2006, 11:34 PM

I'm still feeling this rifle out. I fired three shots of 92 gr 7828 without the flash tube and got similar velocities as with it but the three shots were in a perfect 3" horizonal stirng with only a slight vertical dispersion.

I know I'm close when that happens. A grain or so above or below that will shift the spread from horizonal to vertical or vise versa then dropping back maybe a half grain will result in a symetrical group.

I went up a grain. Group was a nice triange about right a 1 MOA and a volicity of around 3100. Still no pressure indicators on the cases. The RSI said about 63000 PSI.

My feelings are that the 250 and maybe the 275 grain bullet is what the 338 RUM was made for.

RUMLUVER · #**129** 08-13-2006, 03:58 PM

I agree! The .338 RUM was born to be heavy hitter!

royinidaho · #**130** 08-13-2006, 06:09 PM

BTW, all shots are at 200 yds. That's the closest distance I shoot.

Cause that's where the backstop is

royinidaho · #**131** 08-16-2006, 11:21 PM

Just finished my first pillar bed job. Followed it w/a skim job. Looks and feels really good. Will see if shooting improves. Bedding has another 12 hrs to cure. That means by 1000 tomorrow I could be shooting

If I didn't have to make some money first

RUMLUVER · #**132** 08-17-2006, 10:09 AM

I will also be doing my first pillar bedding job in a few days. The stock is for my new .264WM. I hope all goes well.

royinidaho · #**133** 08-17-2006, 10:43 PM

You'll have no problem. Just think it through first. Once you get going it all makes sense.

Does your RUM torque a bunch. Mine seem to want to twist about a quarter turn to the right or is it the left.

and I hold it pretty firmly. This is off of a pedestal rest.

I'm working on an above the bore bipod with a bit of a wide stance hopefully it will help w/looooonnnnngggg range.

With 93 gr of 7828 I'm getting about an average of 3080 FPS MV for 3 shots today But the battery in the chorno was running low and pooped out after tose three shots. The chrono may show them a little slower than they were.

Pressure was around 60000 PSI which may be actually 62000 or so but there were not pressure problems as indicated by primer markings and case extraction.

Accuracy is right around MOA @ 200.

RUMLUVER · #**134** 08-18-2006, 10:35 AM

To answer your question about the torque from the RUM it's YES!!! all 3 of my RUM's had a jump high and to right. The amount of movement went up with caliber and potentcy of ammo. I have become accustom to a real firm hold with the .338. I like your idea of the above bore tripod as usual let me know how it turns out. I just may adopt a similar set up! On a side note I bought some 142gr SMK's for my .264 and are long and skinny! They make me think of sleek areodynamic fighterplanes when I look at them. I want to do some loooong distance shooting with these when I'm done with my rifle. These bullets have a B.C. of over .590 when fired at at velocities between 2800 & 2900 fps so the should fly fast ,flat and a long ways out there.

royinidaho · #**135** 08-20-2006, 01:28 AM

Been shootin' the 338 RUM today.

Found the max pressure level at about 65000 PSI. At this point the extraction pressure was only slightly noticeable and primer seating was still good. Above that @ 65700 PSI everything was more noticeable especially loose primer when seating. At 73200 it was smack the bolt handle hard and smack it back to get it started. (Sure wish I had some Win cases).

Load was 91.5gr IMR 7828, Sierra 250gr Game King. Base of case to ogive was 3.041". And it didn't group worth a crap.

Got the Hornady 225 SP Interlock shooting 94gr 7828, Base to ogive 2.889"
3 shots @ 200 adjusted back to 100 was 0.612" Velocities of 3097/3097/3102. PSIs of 61600/61020/64924

It seems from my development and another fella shooting a 338 wildcat that 7828 does best at max loads.

It will be a miracle getting the 250gr bullet anywhere near 2900 (only 70 more FPS than the 338 Win Mag barrel)

Have only tired 7828 and H-1000, so far. Maybe Retumbo for the 250s?