.338 R.U.M. fans

[RUMLUVER]

Roy,

I was able to get within +or- 10fps of 3000fps with a 250gr Iterlock using 90gr of IMR7828 and 90gr of H4831. Both loads produced sub MOA accuracy.

[royinidaho]

RUMLUVER,

How confident are you w/your chrono readings? I can't come close to those velocities with that amount of powder or for that matter, any amount of powder.

[RUMLUVER]

I am very confident in my results I have achieved those results on more than one occasion and the results were fairly consistant. My biggest swing was 20fps but always +or- 10fps of 3000fps. I am going to do it again soon because I'm going on an antelope hunt and temps are warmer during this season so I want to see how this will change my results. I'll let you know how it comes out.

[royinidaho]

Bought some Retumbo Monday and some RL-25 earlier today.

I wasn't impressed w/Retumbo's numbers so I started with the RL-25

From using the RSI pressure trace I'm pretty confident of recognizing the pressure sign from case extraction. I set up the chrono and started shooting.

I used the same two cases for this whole deal for analness.

RL-25, Sierra 250 Game Kings, seated to 3.041 base to ogive(if that'w what you call where the bullet is 0.338 diameter). Federal 215 Primers and neck sized cases.

90gr - 2822
91gr - 2883
92gr - 2902
93gr - 2949
Here's where I began to think that 3000 fps was achieveable.
93.5gr - 2977
94gr - 2983
94.5 - 3009
94.5 - 2993
94.5 - 2995

OK, now I'm comfy w/the velocity. Just beginning to see/feel/sense pressure signs in heat of day w/cartridges and rifle at afternoon temperatures.

The group looked prommising
94.5 -

I have a lot of seating depth to work with. The bullet base is at the base of the neck. The powder level is at the base of the shoulder.

I'll hook up the RSI and do further testing but it shouldn't need to be much.

Besides the average velocity of 2999 FPS there was a spread of +10 and -9 from the average which is much better than I was able to achieve with the Win Mag.

Also, after a scope adjustment the last two shots went into 0.55" @ 200.

Tomorrow well see if this is a fluke or not but I'll grin myself to sleep tonight.

[RUMLUVER]

Glad to see everything is working out for you now. It will be intresting to see what pressure your at with that 94.5 of RL 25. I might just try working with that and my 250gr Interlocks. I havn't tried RL 25 with them yet so it would be nice to see if could duplicate that accuracy also. Keep me posted !

[royinidaho]

A bit of data from this afternoon:

All loads 250gr Sierra Game Kings, 94.5gr RL-25, GM-215M Primers, Neck sized and numbered cases. Note the difference in seating depths.....

Shot Case Vel COAL Primer to ogive.
1 1 3034 3.24"
2 2 2995 3.24"
3 3 2991 3.24"
4 4 2958 3.072"
5 5 2932 3.072"
6 6 2951 3.072"
7 7 2904 3.016"
8 8 2927 3.016"
9 9 2915 3.016"

Pressure was in the low 60Ks for shots 1-3 and decreased uniformly to low 50Ks for shots 7-9. That was kind of a surprise

Accuracy was not good. 3-4" @ 200 yds.

[RUMLUVER]

Very intresting indeed and I'm glad to see that you have obtained the 3000fps. Now to get the accuracy with the desired speed.

[royinidaho]

Sorry its only one data point but it was fun go get.

also how does one post 2 pics on same post????

Pre-tubb final finish process completion. (approximately 150 rounds fired:

[royinidaho]

after shooting the last 5 #4s and the last 5 #5s on one sweet early fall morning:

[RUMLUVER]

Some mighty nice shooting there Roy! I realy liked that 225gr Hornady target I get similar results with 92grs of 7828 but just a little bit faster but not enough to make a difference. I hope to be able to shoot some more before I go back to work but the wind hear in North Dakota won't quite blowing it's at 40mph.

[royinidaho]

Finally gotter all done, well, pretty much.

Was at the local county fair. Some kid was painting album cover type things w/paint cans and torching them off to dry the paint. It was pure inspiration.

He did the paint job. Cost me 35 Bucks.

Just finished the drag bag/shooting matt and the short sticks. Gave it all a good test this morning while doing some drop chart testing.

Those HOR 225s sure shoot good!!

[RUMLUVER]

Looks sharp Roy! And it souds like it shoots as good as it looks!

[royinidaho]

Found a box of Hornady's new 250gr BTHP Match bullest #33361

Cost me 31 bucks + and a 60 mi round trip just to see what they looked like.

Selected a seating depth as determined by the bullet seated by the riflings.

Stoked three with the same load I used for the Nosler PTs. (94.5gr RL 25 & GM515M primers). These were fire forming loads as I had just formed them from 300 RUM cases.

The three shots strung about 4" vertically @ 200 yds. No chrono readings. Dead battery

Kyped batter from LRF for next shots.

Loaded 3 fire formed cases w/95gr RL-25 and the fed primers.

Shots went 2978/2940/2958 and tried to from a group but 1 shot was 2.5" high.

Things indicated that as powder went up vertical stringing went down so.....

Loaded 3 more w/96gr RL-25.

Shots went 3000/3015/3020 and into about 1.28" @ 200.

Will see if there is improvement with 96.5grs of powder but 3000 FPS MV is adequate for me but I'll take more if I can get it.

[RUMLUVER]

Looking good Roy I wish I had more time to play but I had to go back to work. I will do some in about 2 months.

[RUMLUVER]

Roy finally my .264 is done and I am hoping to go to the range this Sunday to see how it shoots. I will post pictures when I can. I am so happy Shooting it is all I can think about while I'm at work!