Originally Posted by MontanaRifleman
I dug up an old (4 yrs) thread on this subject and wondered if anyone might have some experience or anything to add.
Barrel wear with 7mmRUM
In the article, Kirby says he believes the large overbores can get improved barrel life by switching from the stick powders to the newer ball powders which he believes are fairly temp stable and will burn "clean" at higher pressures. These include Ramshot Magnum and AA8700. He says these powders dont burn as "hot" as the stick powders.
Kirby, sorry to take your name in vain,
but I find this a fascinating subject, especially scince I have a 300 RUM and am considering a 7.
Anyway, was wondering if anyone else has any experience and insight with this that they could share on the subject. Any one using these powders in their Ultra's?
The military did a lot of testing to determine what type of powder was best for long wear
and determined that the ball powder seamed to be less abrasive on the throat of barrels.
They felt that it was the shape instead of burn rate or temperature. The stick powders eroded
faster because of the sharp edges on the cylindrical powders.
They were also looking for a certain port pressure for there gas guns and the ball powder
was easier to predict at barrel lengths to the port.
As to the issue of cooler or less temperature sensitive , There are some ball powders that
are extremely temp sensitive. (One of my favorite powders ,H414 is one of those) but there
are some stick powders that are also heat/temp sensitive.
I feel that poor barrel maintenance has more to do with barrel ware that any other one thing.
Case capacity,velocity,barrel temperature, cleaning,type of powder, amount of fouling all
contribute to barrel ware. That is the reason the military tries to hold velocity to around
3000 ft/sec, use ball powders and know that the rifles cannot be cleaned every time they
are shot. And also temperatures will sometimes be high during a fire fight.
I have barrels that use stick powder that have over 20,000 rounds through them and accuracy
is still sub 1/2 MOA.
On the big Magnums I use a lot of H 50BMG (Stick) and H869 (Ball) depending on what the rifle
likes and don't worry about the barrel getting 20,000 rounds through it because they are
hunting rifles and with proper cleaning they should last a lifetime.
So enjoy the rifles and feed them what they like.
Just my 2 cents
J E CUSTOM