[USAF452]

A few weeks ago I put a pre-owned Remington 700 SPS Tactical .308 on layaway. The price was reasonable compared to new, and I was able to talk them down an additional $50 because it had been on their shelf for a while before the recall. I kept seeing the rifle on the shelf and was wondering why it hadn't been snatched up. I've looked it over several times, had the bolt out, cycled the bolt, and was allowed to dry fire it a few times just to be sure of its function. Everything appears to function normally. The rifle has been through the recall so the trigger isn't an issue.

Here's my question:

I know that there is supposed to be a "break in" on bolt rifles. What would be recommended I do differently because this is a used gun?

Also, this has a 20" barrel. I've read that most bolt guns in .308 get optimum ballistic performance using a 165-168 grain bullet. I'm assuming this is using a 24 inch barrel or longer. Would having a shorter barrel mean I would likely be getting optimum performance from a 150-160 grain bullet?

 

[Dirty Rod]

The break in debate will go on forever but, if you are going to break in a barrel, it needs to start from the first round. If yours is used, you have to assume its got more than a few rounds through it so any benefit you were going to get from breaking in the barrel is gone. Just go shoot it.

Optimum bullet weight is based on barrel twist not length in a rifle. The extra 4" gets you an extra 150-200fps at the muzzle. The barrel twist should be stamped on the barrel.

 

[diyj98]

The break in debate will go on forever but, if you are going to break in a barrel, it needs to start from the first round. If yours is used, you have to assume its got more than a few rounds through it so any benefit you were going to get from breaking in the barrel is gone. Just go shoot it.

Optimum bullet weight is based on barrel twist not length in a rifle. The extra 4" gets you an extra 150-200fps at the muzzle. The barrel twist should be I stamped on the barrel.

I agree!

 

[Knightslugger]

Optimum bullet weight is based on barrel twist not length in a rifle. The extra 4" gets you an extra 150-200fps at the muzzle. The barrel twist should be stamped on the barrel.

Which will get you more RPM on the bullet... which equates to a more stable flight.

2600 fps in 1 - 10" twist = 3120 fps in 1 - 12"

 

[Dirty Rod]

2600 fps in 1 - 10" twist = 3120 fps in 1 - 12"

You'll have to educate me on that one. I've never heard of spin rate providing more velocity. Generally velocity is related to charge weight so I don't understand how changing the twist provides more pressure. A 500fps velocity increase by going from 1/10 to 1/12 is a bunch.

 

[Knightslugger]

You'll have to educate me on that one. I've never heard of spin rate providing more velocity. Generally velocity is related to charge weight so I don't understand how changing the twist provides more pressure. A 500fps velocity increase by going from 1/10 to 1/12 is a bunch.

you misunderstand. the figures above were referencing bullet stability. the same RPM can be achieved in a 1-12" barrel when the projectile leaves the barrel at 3120 fps as it would traveling slower (2600 fps) in a 1-10" barrel. What you said about the length of the barrel does weigh into the speed of a projectile. a longer barrel will generally produce faster projectiles with the same load.

The twist rate of a barrel does not, by itself, dictate the stability of a projectile in flight.

a 185 gr Berger Juggernaught OTM bullet is in the high range of MARGINALLY STABLE in a 1-12" twist barrel at 2450 fps. but add on 4" to the barrel (thereby adding 150-200 fps) and at 2650 it is stable with a SG of 1.5

 

[Dirty Rod]

you misunderstand. the figures above were referencing bullet stability. the same RPM can be achieved in a 1-12" barrel when the projectile leaves the barrel at 3120 fps as it would traveling slower (2600 fps) in a 1-10" barrel. What you said about the length of the barrel does weigh into the speed of a projectile. a longer barrel will generally produce faster projectiles with the same load.

The twist rate of a barrel does not, by itself, dictate the stability of a projectile in flight.

a 185 gr Berger Juggernaught OTM bullet is in the high range of MARGINALLY STABLE in a 1-12" twist barrel at 2450 fps. but add on 4" to the barrel (thereby adding 150-200 fps) and at 2650 it is stable with a SG of 1.5

Got it. For a second there I though I was going to have to chuck my 1/10s. :lol: