can someone tell me what OAL the 284 Winchester would be when loaded with a 140 TSX "on the lands"....I'm contemplating shortening the leade on my reamer. I'd like to get the 140 TSX within .050" of the lands while fitting a 2.80" mag box...if this bullet protrudes below the neck too much I may try the 145 Speer. A friend has taken a moose and a pile of deer with this bullet out of a 20" 7-08 so I know it works.

OAL is totally dependant upon the firearm.

quote:

Originally posted by ricciardelli:
OAL is totally dependant upon the firearm.

wow...now that's a revelation...thanks Steve.

what I'm asking is this "in a standard SAAMI chamber...with standard SAAMI leade..."what would the OAL cartridge length be with the aforementioned bullets "on the lands"?...this will tell me how much to shorten the leade on my reamer to get an OAL of 2.80"...with the bullet, hopefully within .030" of the lands...is that a bit clearer?

Rembo

I think Steve's answer was right on the mark. It depends. Why don't you take a 140 gr TSX and load it to a length of 2.80" and measure it???

Ray

quote:

wow...now that's a revelation...thanks Steve.

what I'm asking is this "in a standard SAAMI chamber...with standard SAAMI leade..."what would the OAL cartridge length be with the aforementioned bullets "on the lands"?...this will tell me how much to shorten the leade on my reamer to get an OAL of 2.80"...with the bullet, hopefully within .030" of the lands...is that a bit clearer?

There is no "standard SAAMI leade" for a cartridge. SAAMI and CIP define pressure limitations (supposedly), and case and chamber dimensions.

The leade is totally up to the manufacturer, tool maker, machine operator, the day of the week, and what part of the menstrual cycle the operator's lady-friend happens to be in.

If you want to create a barrel to work with a specific cartridge dimension (as you have stated you want to do), then you load the cartridge to the OAL you like and machine a reamer to give to the 0.030" distance you desire, and cut the chamber.

However, remember that as the throat erodes, as the reamer wears, and the next batch of Nosler, Barnes, Sierra, Speer, Norma, Hornady, Lapua or whatever bullets will probably measure differently than the batch you have (or don't have) on your reloading bench, then you magic number of 0.030" disappears.

I'll go back to plan A...I chambered a rifle for a friend with this reamer. I'll get him to load a bullet "on the lands" and measure the overall length and note where the base of the bullet sits in relation to the neck/shoulder junction. Then I'll see how much I have to shorten the leade on my reamer to get it into a 2.80" mag box, while hopefully being within .030" of the lands.

Rembo

Don't mean to beat a dead horse here, but it seems to me you're making some false assumptions and taking the long way home. Not all bullets out of the same box will have the same length so measuring the OAL is going to tell you nothing except for the OAL with that one bullet. You need to measure from base to ogive. You have set the OAL at 2.8" so knowing that dimension, subtract a reaonable amount for the above mentioned variation in bullet meplats plus clearance at the front of the magazine box. Since you have the reamer in hand you should be able to arrive at the proper freebore and throat dimensions. JMHO

Ray

quote:

Originally posted by Cheechako:
Rembo

Don't mean to beat a dead horse here, but it seems to me you're making some false assumptions and taking the long way home. Not all bullets out of the same box will have the same length so measuring the OAL is going to tell you nothing except for the OAL with that one bullet. You need to measure from base to ogive. You have set the OAL at 2.8" so knowing that dimension, subtract a reaonable amount for the above mentioned variation in bullet meplats plus clearance at the front of the magazine box. Since you have the reamer in hand you should be able to arrive at the proper freebore and throat dimensions. JMHO

Ray

I certainly realize that this method is "bullet specific"...hence the mention of two specific bullets. The .030" measurement is not written in stone either. I may not be able to get that close. I have a feeling it will have to be closer to .060".

I'll let you guys know how it works out.