It's a 308 ....I ran the LR Varget barrels to 8,000 rds., before chambering another barrel blank, with max loads, never concerned about barrel heat, until it interfered with seeing the target.Sounds like a real barrel burner.
What is a “hybrid case?” Do you have a “hybrid chamber?”
are you single feeding it or putting it in a magazine? If it came from the factory it should be standard length, so I'm wondering why the scrape marks.
Need to get with the times...8 & 9 twists are old news, with long heavy bullets ...need to apply them to the 308 win case, along with hybrid cases for a little extra boost.
Considering I was running a LA 300 WSM and struggled to get 2675 with a 22" barrel and the 225 ELD, are you getting this kind of velocity with a 30" plus barrel?
Yes the 225 gr at 2672 average on this string was LA 30" Bartlein 5 R 308, with Lapua cases.
You should look at getting some 168 ELDs instead of 175s. The 168 ELD has a better BC.
That 2.135 is for a factory 168 ELD load? I never had much luck with the 168 ELD in an M1A.
Glad you brought that up, going to order some from SAC now that I'm thinking about it.
I'm pretty restricted on the OAL because of the magazine. 2.830 is about max and I have no interest in single feeding.
Also, I am not saying that one manufacturer is "more accurate" than another. Ogive measurements are relative (to the tool you are using).
Sorry, I misread you post. Thought you you were talking about seating them out when you said shoot them long.
I've actually wanted to upgrade for a while since I have SAC's headspace comparators, but after seeing the disparity between the diameter measurements, I'm just going to switch everything over.
For me, the biggest reason that I changed was that the Hornadys are aluminum (relatively soft) and the SAC's are stainless (much, much harder).
I just measured the BTO of my 168 and 175 SMK's and there was a .002 difference, the 168 being the longer. BUT. . . . keep in mind there can be a MUCH bigger difference within a lot AND an even bigger difference between lots (like .034"). So, that .002 difference really doesn't help you. Add to that, there's variations in different comparators.
You might think about trying the 169 SMK's??? The 169 SMK BTO's are ~.020 longer than the 168 SMK's and the COAL is about .105 longer. The 169's are tipped and works really well out to 1000+ yds . . . better than the 175's. They can be a little hard to find, but they're out there:
Oh I know all about them. It was the first bullet I tried in the rifle in January with H4895 and it shot lights out, even jumping .117 at mag length, better than any M1A I've ever had, and was still shooting great up until about a month ago with that bullet until I changed lots of powder and the accuracy has gone to shit. Have tried everything, re-working up the load, seating depth changes, cleaning the gas system, barrel, different torque specs on the gas plug, yet the groups are inconsistent and all over the place. Even tried some Federal GMM that I know shot well and it still shoots so I figured I would try a different bullet and powder.
Thank you! I only have the newest Hornady manual and I was afraid the VV may not have the 169 data and I wasn’t sure how close the 168 would be. I greatly appreciate it sir!
I don't have any direct experience with that, but I don't see any reason why it might not work for you.
Different torque on the has plug ? That has that much effect on the m1a ? Interesting. My brother has one.
Fart wrong and it will have an effect on an M1A. One day it will shoot great groups and the next day it won't, very frustrating rifle. Yet I can't live without one.
I've experienced some of the inconsistency with my brothers rifle. I think I've shot it more than he has.
I shoot a lot of 5 shot groups with 4 touching and then one a half to three quarters of an inch away from the group. If I ever figure out how to tune that out, I'll let you know.
It's usually never the 5th shot. Usually 2nd or 3rd and then all remaining shots cluster back into the group.
Just so there's no confusion. . . Hornady's OAL Gauge is actually used to measure CBTO (Cartridge Base to Ogive) to find where the bullet it touching the lands. OAL is usually a reference to Over All Length.
When you look at powder manufacturers page of data, how the cartridges are loaded is usually listed at the top along with COAL (C.O.L.) with the barrel length (often 24") for velocity reference purpose. They do not list CBTO since everyone's chamber can have a very different freebore and different comparator inserts have various diameters. Like what you see here on Hodgdon's website.
Yes. But when doing that you'll want to do it in small increments, starting well below the powder company's maximum recommendation (like ~10% below) and monitor for pressure signs as you increase powder charges.
