Where's the failure?
Quote from Reloader on May 14, 2012, 4:22 pmlet's break this down into smaller steps. Focus on the empty brass first. Size a case, remove it from the loader, and wipe the lube off. Drop it into the case gage. The primer end of the case must be flush with the lower step at that end of the gage, and the case mouth must not stick out beyond the top step at the case mouth end of the gage. If this is all correct, drop this empty piece of brass into the chamber, see if the bolt closes then allows easy extraction of this empty case.
2.810" is too long of an overall length for the 168 grain BTHP bullet. This length is the absolute maximum length for .308 Winchester. 2.775" is the recommended OAL for a loaded cartridge using this bullet. It is possible that the bullet was jammed against the rifling, due to variations from one bullet to the next.
let's break this down into smaller steps. Focus on the empty brass first. Size a case, remove it from the loader, and wipe the lube off. Drop it into the case gage. The primer end of the case must be flush with the lower step at that end of the gage, and the case mouth must not stick out beyond the top step at the case mouth end of the gage. If this is all correct, drop this empty piece of brass into the chamber, see if the bolt closes then allows easy extraction of this empty case.
2.810" is too long of an overall length for the 168 grain BTHP bullet. This length is the absolute maximum length for .308 Winchester. 2.775" is the recommended OAL for a loaded cartridge using this bullet. It is possible that the bullet was jammed against the rifling, due to variations from one bullet to the next.
Quote from Reloader on June 4, 2012, 3:09 amSo the good news is after two batches of 20 rounds I've had no problems. The bolt consistently goes forward and locks, fires, unlocks, and ejects fine. The only thing I noticed do far is that before firing, when I load the rounds and cycle them through the rifle, some still bind up and take a little muscle to get the charging handle back and eject the round. This may be my fault however if I am not gripping the release lever hard enough. My next batch will be 50 and I will cycle them all and see what happens. I'll keep you posted...
Right now I am loading the following;
168gr. BTHP Match Ammo
Federal or Remington .308 brass
43gr. of Varget powder
Winchester primer
OAL: 2.775" +or- .005"Rifle is a 16" AR-10 chambered in 7.62 NATO
If there's any suggestions I'd be open to hear it?
So the good news is after two batches of 20 rounds I've had no problems. The bolt consistently goes forward and locks, fires, unlocks, and ejects fine. The only thing I noticed do far is that before firing, when I load the rounds and cycle them through the rifle, some still bind up and take a little muscle to get the charging handle back and eject the round. This may be my fault however if I am not gripping the release lever hard enough. My next batch will be 50 and I will cycle them all and see what happens. I'll keep you posted...
Right now I am loading the following;
168gr. BTHP Match Ammo
Federal or Remington .308 brass
43gr. of Varget powder
Winchester primer
OAL: 2.775" +or- .005"
Rifle is a 16" AR-10 chambered in 7.62 NATO
If there's any suggestions I'd be open to hear it?
Quote from Reloader on December 6, 2012, 2:30 amAre you getting reliable results using Varget in the powder throw, or are you hand weighing each charge? I have not had good results with Varget type powders so I hand weigh each of my precision 308 loads and run the 650 more in single stage mode. It sounds like a headspace issue... ie resizing die. If you have a headspace guage, take a few fired cases and measure the headspace on those. If you are talking about an AR-10 platform, subtract AT LEAST .003 inches of the fired case and use that as a minimum number. I personally just "bump the shoulders back" using a full length resizing die. Example... a fired case from my AR-10 shows a headspace of 1.268, so I will bump the shoulders back to 1.265. The number does not matter, what matters is that you get it back at least .003 for gas guns, some guys say minimum of .004. Just a little bit of headspace being off will make a big difference in performance of the gas guns. Good luck
Are you getting reliable results using Varget in the powder throw, or are you hand weighing each charge? I have not had good results with Varget type powders so I hand weigh each of my precision 308 loads and run the 650 more in single stage mode. It sounds like a headspace issue... ie resizing die. If you have a headspace guage, take a few fired cases and measure the headspace on those. If you are talking about an AR-10 platform, subtract AT LEAST .003 inches of the fired case and use that as a minimum number. I personally just "bump the shoulders back" using a full length resizing die. Example... a fired case from my AR-10 shows a headspace of 1.268, so I will bump the shoulders back to 1.265. The number does not matter, what matters is that you get it back at least .003 for gas guns, some guys say minimum of .004. Just a little bit of headspace being off will make a big difference in performance of the gas guns. Good luck