Finally...time to test the 375 rum and the 320 ce

[Outlaw6.0]

Keep that info coming! You've definitely got my attention. I might suggest taking the load you have now & stretching it out to 300-500 & see how she shoots.



t

 

[HARPERC]

Ok...ok...Harp I agree with you. I knew the 320 ce bullets were going to take a little tweak so that's the reason I bought the 260 accubonds. I knew I could get the accubonds to shoot the first day at the range so that's my logic. I wanted to have a bullet ready to go for sure and have completed that mission. However the work up on ce's is going unexpectingly good so I might just roll with them!!

Makes sense!

 

[Doublezranch]

Tonight I'm going to load 3 sets of 3 at 93.5 grains. One group will be 20 thou longer, 40 thou longer, and 60 thou longer and see if there's any improvement. I'm headed out of town for the long weekend so results will have to come next week.

 

[Doublezranch]

Here is a diagram that Cutting Edge sent me on their preferred way to seat the bullets.

 

[Doublezranch]

Another great day at the range. Shot the 7828 ssc ladder with terrible results. Accuracy was a less than perfect 1 to 1.5 MOA at its best group. Pressure showed it's ugly face sooner than expected around 92.5. Velocities were as follows:

7828 ssc
90 - 2576
90.5 - 2600
91 - 2615
91.5 - 2626
92 - 2650
92.5 - 2670
93 - 2700
93.5 - 2725
94 - 2740

Lack of accuracy and overpressure plagued this ladder. RL 22 will be the top dog. Now I'll tweak seating depth to see if I can tighten the group some.

 

[Lefty7mmstw]

Dang, all this playing with the 375 rum makes me want to ream the chamber out on my h@h. I'm not going to, but I want to.
I've got 2550 fps on tap at present with the 300 tsx and 4320, and I've got to load some with v540 as per the barnes book; they should hit 2650 fps with the little h@h.

 

[Doublezranch]

I would have never guessed in a million that the RUM would be able to push that big of a bullet, that fast, with sustainable speed and accuracy. It sounded like a missle going down range. People would stand back from their benches to watch the bullet travel and blow a 2x2 inch hole in the burm. Then everyone has to see what your shooting and a hour at the range turns into 3. Oh yeah, I wasn't able to find any bullets, but they must expand like crazy cause it leaves a pretty good size hole in the burm.

Should be very interesting to see how the bullet reacts sitting closer to the lands. This caliber does beat you up a bit. Even with a ASSASSIN tuned brake on the end of the tube, the recoil managed to pull the bipod and front swivel stud clean out of the stock. Needless to say I over bored the hole and replaced it with a swivel/nut combo. Shouldn't be anymore issues.

 

[benchracer]

Dang, all this playing with the 375 rum makes me want to ream the chamber out on my h@h. I'm not going to, but I want to.
I've got 2550 fps on tap at present with the 300 tsx and 4320, and I've got to load some with v540 as per the barnes book; they should hit 2650 fps with the little h@h.

The 300 grain CE is a very good match for the H&H. RL-17 will get you to 2750 or so from a 24" barrel, which will just put you in the accuracy node for that setup. With a .750 G1 bc, that combo will put the "little" H&H in a completely different performance category.

Of course, the RUM will do the same with a heavier, higher bc bullet, but the H&H with the 300 CE is still pretty respectable.

 

[CB11WYO]

Wow, good read this was!

Couldn't resist so I ran the ballistics real quick for 6000' (my home)...

Yer still supersonic and packin' 1000 ft/lbs of energy at 2200 yards, what a hammer (using a velocity of 2750)

 

[royinidaho]

Might want to put an APS Pain Killer brake on her.

Makes shooting a 350 grain offering ahead of 140 gr of powder quite pleasurable.

About an inch of recoil then she stops and " seems" to pull ahead a bit.

 

[Doublezranch]

I'm a Assassin guy all the way. The brake has allowed my 12 year old a chance to shoot all my big ultras. Jerry does a phenomenal job tuning and tweaking the brake to make it disspurse as much gas as possible in a very stratigic manner. As you said Roy those pain killers do a pretty awesome job too. I've just had very good luck with the assassin. As everyone knows who shoots these big guns, recoil only goes away when you don't pull the trigger.

 

[Lefty7mmstw]

I guess I'm an oddity. I've had others tear up when they pull the trigger on my rum (hard rubber pad- no brake-300rum), but I'll go prone with her and it doesn't phase me a bit. Now if I shoot righty I'll feel recoil a bit more, but I still get the job done....

might have to play with the 300 ce bullet benchracer is talking about.... could be fun.... with my rifle I'd be surprised to hit 2650 though... she does the job but doesn't seem to be overly fast for what I feed her.

 

[benchracer]

I guess I'm an oddity. I've had others tear up when they pull the trigger on my rum (hard rubber pad- no brake-300rum), but I'll go prone with her and it doesn't phase me a bit. Now if I shoot righty I'll feel recoil a bit more, but I still get the job done....

might have to play with the 300 ce bullet benchracer is talking about.... could be fun.... with my rifle I'd be surprised to hit 2650 though... she does the job but doesn't seem to be overly fast for what I feed her.

The CE bullets tend to run about 50 fps or so faster vs similar cup and core bullets of the same weight, with the same powder charge. Depending on where you top out with RL-17 and a standard 300 grain boat tail bullet, you might be surprised.

If the CE and RL-17 won't take you to 2750, the next lowest node (I am assuming you have a 24" barrel) will fall between 2560 and 2620. Even without the speed, the bc advantage over the other .375 bullets that are available is still worthwhile, IMO.

The downside, though, with the CE bullets is that they produce very long base-to-tip COAL's. In most rifles, this requires single feeding. Even in a true magnum length action (like the CZ 550), it is only possible to load one round with the bullet laying on the feed ramp and one in the chamber. For the gain in capability, I consider that to be an acceptable trade-off. Not everyone feels that way, though.