Barrel life of the 7mm Rem Mag with respect to bullet weight

[jonesy]

Hey, I'm new here but have been reading around on the forums for quite awhile. I've had a Savage 116 chambered in 7mmRM for about 2 years now, and I just upgraded to a Shilen BBL in the same chambering.

My concern is that 7mmRM tends to burn out barrels quite quickly in comparison with .308 et al, and that I may or may not be doing what I need to do to maximize my barrel life while not sacrificing the accuracy of my handloads.

I currently reload Berger 168 VLD's around 3015 fps, but I would like to know if there is another bullet choice that will enable me to elongate my new (and quite expensive) barrel's life.

So, I have two questions:

1. How many rounds should I expect to get out of this barrel before the accuracy of the rifle starts to deteriorate (i.e. the rifle stops shooting sub 3/4 minute, which it is capable of now)?

2. Could I go to a heavier bullet to decrease the amount of powder in my loads (and decrease the muzzle velocity just a tad) to increase my expected barrel life?

I've tried to Google this issue and I've searched around on the forums here with no hits that really apply to what I'm asking.

Also a quick note: I have been loading 168 gr Bergers since I got the rifle. I would be willing to try another bullet that you all suggest, especially since I RARELY shoot past 400 meters. I'm planning on shooting out to 1600 at some point, but I just don't have access to a long enough range here in Kentucky.

Thanks for your time,

jonesy

 

[Tickle]

You may want to check this out. http://www.longrangehunting.com/forums/f17/7mm-rem-mag-barrel-life-70091/

I only shoot 300 win mag, but this is worth reading.

 

[turbo54]

Beware of "formulas".

It comes down to pressure, heat, and time. An increase of any of these factors will cause increased erosion.

Different powders create different amounts of heat, but assuming equal heat and pressure, a lighter bullet that accelerates faster, will decrease the time the heat/pressure can erode the throat.

However, lighter bullets take more powder and that increases heat input.

I have no idea where the "sweet spot" is for optimizing throat life, but a safe bet is light bullets at relatively low speeds are going to allow a barrel to last the longest.

 

[jonesy]

Thanks for the replies. I had previously read that thread from LRH and did find it to be interesting, I just don't know how much it helps when it comes down to what kind of loads to run to maximize barrel life.

As for light bullets at slow speeds, that would be sacrificing accuracy that I don't think I can sacrifice right now. Maybe at 100 meters it wouldn't be so bad, but....

I'll probably just move up to a heavier bullet with less powder. That way I know I'll be producing less heat. As for pressure, there's really no way to quantify what's happening unless I've got a gauge (which I don't and I don't plan on getting one either).

jonesy