2950fps VS 2850fps barrel life question

[hikfromstik]

I'm trying to find if shooting 130gr berger AR hybrid at 2950fps with reloder 16 in a 24inch creedmoor buttoned barrel will drastically shorten barrel life VS 2850fps with H4350 (more pressure signs ). If it only shortens it by a couple hundred rounds then I don't care , because it's my accuracy load ( single digit ES / shoots in the .3's ). I'm no expert on barrel wear so someone that is please enlighten me. I'm at the conclusion that speed isn't what burns barrels up , but instead is the pressure used to get to those speeds. SO if I can use a lower pressure load to get a bullet up to 2950fps wouldn't this be less throat erosion ??? BTW I'm using 43.2gn of Reloder 16 ( 0.8gn under Alliant published max ). It seems that Reloder 16 with lighter bullets ( 120-130gr ) will achieve higher velocity with less pressure signs than other powders in my experience. This the same logic that some are mentioning about Reloder 26 and increased barrel life .

 

[DirtySteve]

Barrel heat is also a consideration for barrel wear. The cooler you keep your barrel the longer it will last. Shoot a slower velocity bullet but bang out long strings of shots will cause more damage than fast velocity and more time to cool between shots. I am no expert either but that is my take on it. Pressure and heat. More powder equals more pressure and heat. Long shot strings more heat. I am sure others with more experience shall chime in shortly.

 

[hikfromstik]

If heat softens metal then the hotter the throat would equal more wear . So if a powder will have lower throat pressure but still get bullet to let's say 3000fps then barrel life should improve over other powders . If any one has any Reloader 16 quick load data let's hear it .

 

[Bart B.]

This is based on the barrel starting out shooting 1/4th MOA average at 100 yards then degrading 50% to 3/8ths MOA. Hotter powders have up to about 10% shorter barrel life numbers than cooler ones.

 

[Bart B.]

Regarding barrel heat and barrel life, I've seen no difference between 308 Win barrels with 40% to 50% of their rounds were rapid fire 10 shot strings in a minute and the rest slow fired once every 30 to 40 seconds apart compared to those where all shots were slow fired 30 to 40 seconds apart.

 

[DirtySteve]

I have about 8,100 rounds through my 308 and I can not tell of any loss in accuracy. Most shots have been 44.3 gr Varget and a 175 gr bullet. Mostly SMK but some Bergers.. It has an M40 contour and is shot in F-class matches.

 

[hikfromstik]

View attachment 1045798
This is based on the barrel starting out shooting 1/4th MOA average at 100 yards then degrading 50% to 3/8ths MOA. Hotter powders have up to about 10% shorter barrel life numbers than cooler ones.
View attachment 1045801

If it's just 10% less rounds then it's worth it to get the accuracy I'm getting . The whole reason I reload is to find the magic node and if my barrel goes in 200 less rounds then I see no reason to change anything. Thanks for the info .

 

[Bart B.]

US 30-06 and 7.62 service rifle barrel lives were about 10,000 rounds. That's when their throat erosion gauges went into the "REJECT" mark. 1/10th inch further for every 1000 rounds.