LR 308 leade or throat length.

LeadHead · June 4, 2012, 07:40 AM

I have a DPMS Recon 308 1 in 10" twist 16" barrel. Rifle has about 300 rounds through it. Accuracy is not what it should be with factory ammo so I wanted make some reloads. DPMS says 1.5" @ 100 yards. I used my COL gauge and the measurement is 2.915. I did it 6 times. Bullet is a Matchking 168gr. This measurement seems to long to me. Is it possible the throat is cut to long or is this average for this kind or rifle? Is there a rule about how much bullet should be seated into the case? My plan was to load some 168, 175 and 180gr. Thanks, Rich

243winxb · June 4, 2012, 12:39 PM

http://www.saami.org/PubResources/CC...Winchester.pdf from www.saami.org If you check the SAAMI drawing, it may give you an idea. Measuring from the cartridge head/base to ogive of the bullet is the measurement you need. For an auto loader, i would want the bullet to make full contact with the neck. Seating the bullets to long will reduce neck tension & may result in crooked bullet from hitting the feed ramp.

**Unclenick** · June 4, 2012, 02:54 PM

Depends on your chamber. Clymer says the freebore is 0.075" on their match reamers, 0.090" on their standard SAAMI reamer, and 0.150" on their 7.62×51 reamers. That makes a difference. Lots of guns shoot just fine with some bullet jump, though.

In your shoes, I would back down to a starting load and run through Berger's exercise for VLD's for hunters rather than target shooters (you're not going to jam the lands loading from a magazine anyway). Load singly and see if you don't find a better COL for your chamber?

LeadHead · June 5, 2012, 06:36 AM

Thank you both for the useful info.

June 4, 2012, 07:40 AM	#1
LeadHead Member Join Date: February 10, 2006 Posts: 17	LR 308 leade or throat length. I have a DPMS Recon 308 1 in 10" twist 16" barrel. Rifle has about 300 rounds through it. Accuracy is not what it should be with factory ammo so I wanted make some reloads. DPMS says 1.5" @ 100 yards. I used my COL gauge and the measurement is 2.915. I did it 6 times. Bullet is a Matchking 168gr. This measurement seems to long to me. Is it possible the throat is cut to long or is this average for this kind or rifle? Is there a rule about how much bullet should be seated into the case? My plan was to load some 168, 175 and 180gr. Thanks, Rich

June 4, 2012, 12:39 PM	#2
243winxb Senior Member Join Date: July 26, 2011 Location: USA Posts: 1,730	308 win. Throat/Leade http://www.saami.org/PubResources/CC...Winchester.pdf from www.saami.org If you check the SAAMI drawing, it may give you an idea. Measuring from the cartridge head/base to ogive of the bullet is the measurement you need. For an auto loader, i would want the bullet to make full contact with the neck. Seating the bullets to long will reduce neck tension & may result in crooked bullet from hitting the feed ramp.

June 4, 2012, 02:54 PM	#3
Unclenick Staff Join Date: March 4, 2005 Location: Ohio Posts: 21,063	Depends on your chamber. Clymer says the freebore is 0.075" on their match reamers, 0.090" on their standard SAAMI reamer, and 0.150" on their 7.62×51 reamers. That makes a difference. Lots of guns shoot just fine with some bullet jump, though. In your shoes, I would back down to a starting load and run through Berger's exercise for VLD's for hunters rather than target shooters (you're not going to jam the lands loading from a magazine anyway). Load singly and see if you don't find a better COL for your chamber? __________________ Gunsite Orange Hat Family Member CMP Certified GSM Master Instructor NRA Certified Rifle Instructor NRA Benefactor Member and Golden Eagle

June 5, 2012, 06:36 AM	#4
LeadHead Member Join Date: February 10, 2006 Posts: 17	Thank you both for the useful info.