7 mm lrm
- Thread starter ann brezinski
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Love reading these threads on all the different 7mm wildcats you guys play with. Out of curiousity, it seems like not many people shoot the 7mm rem ultra mag... you all seem to shoot stw's, rem mags, dakota, wsm's, 7/300wm, 7lrm, etc. maybe i just miss threads about the 7 rum, or is there something you guys don't like about it?
Guinness
Well-Known Member
Since I don't have the background a lot of these folks do I won't go into any detail but I think the reason the 7mm RUM isn't considered too often is because it is somewhat (significantly?) overbore. In other words, the case holds more powder than can be efficiently burnt in a 7mm bore barrel even if the barrel is 28+ inches long. The increased performance of the 7mm RUM comes at a cost as the overbore decreases the life of the barrel, at the throat, more rapidly than other more efficient chamberings. From the research I've conducted it seems the performance vs barrel wear isn't a worthwhile tradeoff unless you really want, or need, every last fps of muzzle velocity.
I had three 7 RUMs. A Sendaro, a LSS and one I had installed on a Rem 700 using a PT&G reamer. The last one was used for a head to head comparison with a 7 STW both made on Remington takeoffs formerly in 7 Rem mag. Just like the Sendaro and LSS the two comparison barrels were 26" long.
I used 168 gr bullets in the STW and RUM. With max safe loads the RUM beat the STW by 50 fps. I concluded that the 7 RUM is best served with a 30" or longer barrel.
Other considerations with the 7 RUM:
The factory chambering has a very long throat. The round won't fit past the feed rails of model 700s that were not made for a RUM case. Barrel life is fairly short and it has the most recoil.
I will say it was easy enough to find accurate loads for all three. Two of my friends bought the Sendaro and LSS and are happy with them. They only shoot them on hunts.
I am currently experimenting with a 7mm/375 Ruger and 180s.
I used 168 gr bullets in the STW and RUM. With max safe loads the RUM beat the STW by 50 fps. I concluded that the 7 RUM is best served with a 30" or longer barrel.
Other considerations with the 7 RUM:
The factory chambering has a very long throat. The round won't fit past the feed rails of model 700s that were not made for a RUM case. Barrel life is fairly short and it has the most recoil.
I will say it was easy enough to find accurate loads for all three. Two of my friends bought the Sendaro and LSS and are happy with them. They only shoot them on hunts.
I am currently experimenting with a 7mm/375 Ruger and 180s.
Very Interesting. So the RUM is just a huge case for 7mm bullets. I wonder if this speculated 7mm 195 Berger bullet that people have been buzzing about is going to drive more guys to the RUM case and 30" barrels to get velocity up?
Dick Tinsley
Well-Known Member
I doubt it! Efficiently is where it's at! A person can only burn X amount of powder in X case for X bullet. I have had dealings with the 7rum an as big of a fan as I am of the 284/7mm caliber an the RUM family the 7mm rum is IMO is a waste of case an powder! I've owned four of them, two I had rebarreled, one I traded, the other one just out an out got rid of because of(1) recoil!(an I'm really not recoil sensitive)(2) couldn't get it to shoot! The owner of it finally rebarreled it! All in all I love a 7mm remington mag, STW an 7/300! Don't know about the 7 Dakota,7/375 ruger. My vote goes to the 7/300 for efficiently an performance in a 7mm!!! NOT SAYING ANYTHING AGAINST THE STW!! Just my choice!! Sorry to get long winded!!
DT
I think we all can sit around and talk about this stuff all day... not possible to get long winded! Very interesting that the 7's just don't need that much case capacity. Remington must not have done the research into the design... where the 300 rum is the start of where you get benefit from the big case, and the 338 obviously shines as well.
I'm actually looking into going to a small little 7mm-08, I think it would make for a great hunting rifle for my two young sons to start out on and for my wife, and then be a great target/range/practice gun for all of us. Not a LR hunting setup, but a very handy, low recoiling rifle, and I also think inherently accurate and extremely efficient.
cohunter14
Well-Known Member
I get a kick out of the 7mm RUM dislike as well. I don't have a 7mm, but if I did, it would be the RUM. The RUM gets blasted for requiring more powder, reduced barrel life, and increased recoil. Well, if you do the cost calculations, the increase in powder cost is less than five cents per round. If you say the STW can take 500 more rounds down a tube than the RUM, you are talking about an increase of less than 25 cents per round. So, for typically 100fps increase (AZShooter's results don't match this, but it is typically what I have heard) you are going to pay 30 cents per round...seems worth it for me, especially in a gun that you aren't going to be shooting a lot. As for the recoil portion, if someone can really tell the difference in recoil between the RUM, STW, or LRM, I would be amazed.
It will be interesting to see how popular the RUM becomes with the introduction of the 195 bergers and the increased popularity of RL33.
It will be interesting to see how popular the RUM becomes with the introduction of the 195 bergers and the increased popularity of RL33.
Dick Tinsley
Well-Known Member
How can one say anything about results of a certian caliber when they don't have one? The OP wanted to know about the 7lrm or 7/300.
If you've never owned one or shot a 7mm rum( don't know if you have or not) yes!!! You can tell the differants in recoile from other 7mm! I think most will agree with that! Just my 2cts!!
DT
cohunter14
Well-Known Member
The 7mm RUM was mentioned, hence me mentioning it. And just because I don't own one of these choices doesn't mean I haven't shot one. If you are comparing the RUM to a 7mag, yes you might notice a difference. RUM versus STW or LRM? Not significant IMO
Dick Tinsley
Well-Known Member
This is the first post of this thread, from the original OP! Don't see anything about the 7mm rum. Also, never said you haven't shot one, just didn't know if you have or have not. Again, if you have( not saying you haven't) shot a 7rum on a regular basis an shot other 7mm, there is an you can tell that there is a differants in recoile! Anyway it's not the RUM that the OP is asking about!
DT
cohunter14
Well-Known Member
The first post about the RUM...followed by many others. I'm not starting my own thread and going off on some tangent here. And like say, the 7mag versus the RUM, yes you can tell a difference. But something like the STW vs the RUM? Nothing significant from what I can tell...
