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weeple2000
05-02-2019, 01:46 AM
How can I find the distance to the lands in a pump action rifle? It has a removable magazine. It's a Remington 760 in 308.

tazman
05-02-2019, 07:57 AM
With the action open, drop your boolit into the chamber and hold it forward against the rifling with a support of some kind(large pipe cleaner, piece of bent wire). Using a small diameter rod down the barrel, measure the distance to the boolit tip.
With the action closed, using the same rod, measure the distance to bolt face.
The difference of these measurements give you the OAL for that boolit, to be seated against the lands of the rifling.
The first measurement must be done for each different style boolit because nose shape makes a difference on when the boolit contacts the rifling.

Wayne Smith
05-02-2019, 07:57 AM
Basic distance to the lands - take sized shell, expand, put in a bullet backwards, chamber. Chambering will push the bullet base into the shell when it hits the rifling. I'm assuming that is what you want.

cwtebay
05-02-2019, 10:41 AM
I use a similar method as Wayne. Size brass, use a dremel to split the case neck length wise, place the bullet into the action gently - close action gently, measure overall length. I repeat this several times. I believe that stepping back 0.003" from that length is where your max COAL will end up with a given bullet. Using a Hornady comparator or similar will take away the ogive discrepancy between projectiles. Good luck!

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Wolfer
05-03-2019, 06:59 PM
In the 2 760s I’ve owned this measurement wont fit in the magazine.

weeple2000
05-03-2019, 08:24 PM
In the 2 760s I’ve owned this measurement wont fit in the magazine.

What measurement is that?

ShooterAZ
05-03-2019, 08:32 PM
What he's saying is that you might might need to seat the boolits to fit and feed from the magazine, whatever length that may be. I have to do the same in my match AR-15's. Not a big deal.

weeple2000
05-03-2019, 08:40 PM
Thanks

PBlover429
05-03-2019, 08:41 PM
This is what you need (the curved one)

https://www.hornady.com/reloading/precision-measuring/precision-tools-and-gauges/oal-gauges-modified-cases#!/

weeple2000
05-03-2019, 08:42 PM
Actually that is pretty much what I do with a bolt. Just force the bullet into the lands with the action. Will the same work with a pump?

gnostic
05-03-2019, 08:51 PM
Years ago, I'd smoke the bullet with a candle, you can see when it touches the lands...

kaiser
05-05-2019, 10:54 AM
I've own several 7600 and 760's, in several calibers, over the years and have not had one where reloaded bullets would "touch the lands" while still feed through the magazine (too long). Accidentally sticking a bullet in the lands of a pump is a "happening" because the action does not have the extraction leverage of a bolt or lever, plus it makes a heck of a mess with the associated powder spill when forced open! I'd be interested if there is a caliber that has a shorter "lead" used in a pump, since all the 76XX series Remingtons are made on the same 30/06 long action.

weeple2000
05-06-2019, 01:05 AM
I've own several 7600 and 760's, in several calibers, over the years and have not had one where reloaded bullets would "touch the lands" while still feed through the magazine (too long). Accidentally sticking a bullet in the lands of a pump is a "happening" because the action does not have the extraction leverage of a bolt or lever, plus it makes a heck of a mess with the associated powder spill when forced open! I'd be interested if there is a caliber that has a shorter "lead" used in a pump, since all the 76XX series Remingtons are made on the same 30/06 long action.

That is interesting you mention that. The rifle in question is actually a 308. The bullet in particular I'm interested in checking is a Lee 200 grain bore rider. If I powder coat it, I am not able to chamber it with my bolt action rifle, if the bullet is seated with the gas check at the base of the neck.

Petrol & Powder
05-06-2019, 07:47 AM
The odds are very good that the magazine and action will dictate the OAL.

kaiser
05-06-2019, 10:18 AM
The 7600’s magazine should be “blocked” for the .308; thus, as petrol suggests, I would make the load to fit the magazine. You might consider crimping the bullet to avoid the cartridge from binding up under recoil.

tazman
05-06-2019, 07:28 PM
I own several rifles that have removable magazines(one is a 760) and in every case, the magazine dictates the OAL. All of them have chambers that will accept a longer OAL than what the magazine will allow.