Originally Posted by MontanaRifleman
J E, you are more knowledgeble on the subject than I am, and for the most part I completely agree with you. But I have read numereous posts that the 300 WSM shows quite long barrel life, 4000+ rounds, and that the 7mm WSM which is very close to the same case has short barrel life 1000-2000 rounds. I find that very interesting. I wonder if that translates over to the RUM cartridges in 7mm and 300? From what I've read it doesn't seem to, at least not to a significant affect. My guess is that a 300 Rum shooting a 210 bullet will probaly slightly out last a 7mm RUM shooting a 180 bullet under similar conditions? Just a guess. It's been my impression that smaller bores in equal size cases burn out faster because they are concentrating that fire power in a smaler area. That may be an overly simplistic view of it. There is probably mor to it. And your assertion that shooting heavier bullets at lower velocities and better powder burn makes sense,
Interestingly, GS claims their bullet design increases velocity withou increasing pressure and their design also facilitates the burn of powder over a longer and larger area of the bore resulting in less throat burning and overall cooler shooting temps.
GS CUSTOM BULLETS - Barrel Wear
Thanks for the complements but there is a lot more that I can learn before I go to the Happy
hunting ground. and I can only speak from over 50 years of experance and you are right
about smaller bullets and bigger cases.
Hear is an example= Take a 375 H&H with a 275gr bullet(The standard bullet used) and place
70grs of powder behind it and you will get 2600 ft/sec velocity and who knows how many
rounds you can run through it 15000+.
Now take the same 375 H&H case and neck it down to 7 mm and blow the shoulder out and
forward into a wildcat like the 7mm STW ( most belted wildcats started life as a 375 and were
changed to personalize them ) and you have a barrel burner because you have made it into
an over boar cartrige and barrel life will not be as long.
Barrel life is determined by many factors so to say a barrel only has 1000 rounds in it
would be unfair and just a guess under the worst case scenario.
I would think that the 7 WSM would have less barrel life than a 300 WSM but not twice or three
times less because of the smaller and faster bullets.
If a barrel is kept clean and carbon is removed as often as possible barrel life will be improved
and accuracy maintained longer.
The 308 is a prime example of the reverse because most match shooters use the 168gr + bullets
and velocity is 26 to 2800 ft/sec using around 42grs of powder and barrels last 20,000 +rounds
before any loss of accuracy.
The first thing I do when a friend brings me his favorite rifle complaining about how the barrel
is shot out and will not group any more is give it a GOOD back to bare metal CLEANING and
most of the time they shoot just like they used to.
And be carefull not to believe everthing you read about claimes of unbelievable high BCs,
velocites,Barrel life ETC because if it seems to good to be true it probably is not true.
By the way ANY Banded Bullet of the same weight and dia. will be slightly faster than a full
bore dia. bullet because of less bearing surface just like flat based bullets have longer
bodys than boat tailed bullets of the same weight and dia. increasing bearing surface
and slowing velocity slightly (a vary small % ) so this is not something new and wonderful
and may have a downside in some applications.
J E CUSTOM