7 rum?

It would be single fed on a defiance and a 30 inch tube.. I would almost bet I could shoot my 230s out of my rum over 3200 and ot would be fine.

The longer tube is only going to give you around an 80-120fps gain.

You're still looking at generating insane heat and temperatures in the chamber and first foot of the barrel, far exceeding anything safe.
 
My brothers 7 Rum is shooting 3170 fps using 195's and RL 50. He said he could get 3200 fps out of his 28 inch barrel if he wanted. I just asked him tonight. I guess I was wrong, thinking it would be hard to get 3200 fps out of a 195.
 
In my opinion the Rum is just too much case for the bullet. There's a point where the deiminishing returns exceed that which is practical. No matter what you do with a 7mm Rum unless you load it down to STW/28 Nosler ballistics it's a barrel eating monster and rather unpleasant to shoot due to recoil and muzzle blast.

Honestly if I were to build another 7mm of any kind other than the STW it would be a 28 Nos, 7 LRM, or one of the 7mm-.375 Ruger wild cats.

I've got a STW closing in on 2000 rounds that still hasn't shown much throat erosion but I've seen Rum's burnt out in as little as 300 rounds.

Of the Rum's the 300 Rum is probably the best performance and tolerability wise.
You're more likely to blow it up than get 500rds through it.
BS. I own one with more than 700 down the factory tube. Shot group of 3 less than an inch at 250 yd last time out. Not gonna BLOW UP GOOD LORD
 
All of the issues with 7 rum in my opinion is reloaders not respecting it. You cant seat bullets on the lands and load like it has .400 free bore. Its not meant to be downloaded or reduced load. It operates best at max and near max 65k pressures with the full freebore jump to the lands. Load it accordingly with propr powders and guess what? No over pressure, no under pressure and dented cases. Great velocities and when you find its sweet spot, good accuracy too.
 
The longer tube is only going to give you around an 80-120fps gain.

You're still looking at generating insane heat and temperatures in the chamber and first foot of the barrel, far exceeding anything safe.
Modern powders are giving greater velocities than old school lines of limitations. N570 for example has at least 100fps over Retumbo in the 300 RUM with big heavies. Reloder 26 is another "yer gunna blow yourself up" with those velocities powder.
 
Hows the primer pockets holding up at that level? Brass manufacturer?
RP 7 RUM stamped brass fired 1x at unknown load(bought used) I have fired it 2x and just deprimed it and nothing fell out so I'm pretty confident my 80 cases will outlast the barrel. Barrel is a 9 twist I was initially going to burn up and get a faster twist but this load is better inside ~1,000 yards.
 
Modern powders are giving greater velocities than old school lines of limitations. N570 for example has at least 100fps over Retumbo in the 300 RUM with big heavies. Reloder 26 is another "yer gunna blow yourself up" with those velocities powder.

Neither of those powders are "blow yourself up" powders unless you exceed the safety limits.

I haven't found any data anywhere suggesting these kinds of velocities are possible with the 195 in the Rum without going far beyond safe pressures with any powder.
 
Warning! This thread is more than 5 years ago old.
It's likely that no further discussion is required, in which case we recommend starting a new thread. If however you feel your response is required you can still do so.

Recent Posts

Top