LR 308 leade or throat length.

LeadHead · June 4, 2012, 07:49 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

jdillon · June 4, 2012, 09:26 PM

The COAL will be limited by the magazine so best to seat to the specified COAL.

tobnpr · June 5, 2012, 04:24 PM

When I bought my reloading setup, I started right off with the LNL headspace gauges and the OAL gauge and bullet comparator.

Likely will make no difference with a semi, because you generally cannot load within .02 of the lands anyway when you're restricted to mag length.

BUT... I would get them anyway (esp. the headspace gauge) to be sure you're bumping the shoulders enuf...important in a semi. Depending on the ogive and weight of the bullet, some will put you closer to the lands than others. The OAL gauge and comparator will tell you exactly what you have, with each bullet type.

Reloading is a BUNCH of experimentation.
Bullet type/length....Have you tried the heavier 175 SMK?
Powder types, and load. What are you using?

Do a search for "load workup"... ladder testing, and OCW procedures are commonly used.
http://optimalchargeweight.embarqspace.com/

When you say "factory ammo"- were you using match, like Black Hills or FGMM? Or, Win White Box...huge difference...

recarga · June 5, 2012, 06:05 PM

My Armalite AR10 likes Remington ame lapua brass and H-4064 and Viht n-140
This will give me .050" MOA , but it took me some time to find It's sweet spot ,

Semis can be. A little pain so I wouldn't worry to much on the C.O.A.L

Also hornady A-max work like a champ.

June 4, 2012, 07:49 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, 09:26 PM	#2
jdillon Senior Member Join Date: October 7, 2011 Location: Southern NM Posts: 141	The COAL will be limited by the magazine so best to seat to the specified COAL. __________________ "Emergencies have always been the pretext on which the safeguards of individual liberty have been eroded" - F.A. Hayek

June 5, 2012, 06:05 PM	#4
recarga Member Join Date: July 8, 2011 Location: big TX,USA Posts: 45	My Armalite AR10 likes Remington ame lapua brass and H-4064 and Viht n-140 This will give me .050" MOA , but it took me some time to find It's sweet spot , Semis can be. A little pain so I wouldn't worry to much on the C.O.A.L Also hornady A-max work like a champ. __________________ IT IS BETTER TO DIE ON YOUR FEET THAN TO LIVE ON YOUR KNEES.

June 5, 2012, 04:24 PM	#3
tobnpr Senior Member Join Date: August 1, 2010 Location: Tampa Bay Posts: 4,556	When I bought my reloading setup, I started right off with the LNL headspace gauges and the OAL gauge and bullet comparator. Likely will make no difference with a semi, because you generally cannot load within .02 of the lands anyway when you're restricted to mag length. BUT... I would get them anyway (esp. the headspace gauge) to be sure you're bumping the shoulders enuf...important in a semi. Depending on the ogive and weight of the bullet, some will put you closer to the lands than others. The OAL gauge and comparator will tell you exactly what you have, with each bullet type. Reloading is a BUNCH of experimentation. Bullet type/length....Have you tried the heavier 175 SMK? Powder types, and load. What are you using? Do a search for "load workup"... ladder testing, and OCW procedures are commonly used. http://optimalchargeweight.embarqspace.com/ When you say "factory ammo"- were you using match, like Black Hills or FGMM? Or, Win White Box...huge difference...