.308 with heavy for caliber bullets

[Silent Sam]

The Lee FCD can change the pressure curve and it stands to reason it can effect peak pressure. Remember your sample size is very small. You are already noting a couple of "looser" primer pockets and an increase in effort to open the bolt. Any sign of high pressure should be heeded. IMO you are flirting with blowing a primer and/or locking up your bolt. Not something I would risk on any hunt. Regardless of tables, calculations, bolt lift, case head and primer appearance 2700fps with a 180gr bullet out of a 20" barrel 308 is a hot load.

 

[kraky1]

Its pretty hard to argue with Silent Sams assesment. I don't think you've hurt a thing with your experiment, but that is a big number even though re17 seems to get another 40 fps over other powders safely in the 308. I've seen factory wby and factory wsm loadings with loose primer pockets after one firing and have seen extractor marks on the brass too. But that doesn't mean its a good idea to give a steady diet of that to a gun.
I load for a buddy's 300 wsm...he had extractor marks with factory loads and 165's at 3120 fps. WE worked up to that level with Re17.....never had an extractor mark...and primer pockets stayed tight for many reloadings. We had good accuracy and we were still 2 grains short of what Alliant said we could go to. And our load matched the results I saw on the internet from alot of other reloaders.....no ne seemed to be up at alliants max.
Based on the results you had I would tend to think you might want to drop back down to the 2620-2640 fps area and assess primer pocket life...but its just my thinking. This has been a learning experience for me too. It was surprising to see results change so much from the 200 grain to the 180 based on what happened with the 200 grain load.

 

[35 Whelen]

:shock: WOW :shock:

 

[kraky1]

Well I was bored tonight and I spent a bunch of time doing Google searches on 308 and re17. The long-range guys are sure playing with it a lot with heavy weight bullets like the 208 Amax. I still feel a little perplexed by how hot that 180 load was.
I'm grasping for straws here but I'm wondering if the chronograph was working perfectly... I'll just throw this out here as an experiment to maybe move it out a few more feet on the next outing?

Here's one guys work up with 208 bullets.... his loads are pretty typical of what I see...
▶ 3:49
https://www.youtube.com/watch?v=Y3ewitwhWlI

 

[LifeAndLiberty]

Chronograph I believe to have been working properly. My father was averaging 2515fps from Winchester 180 grain white box ammo, and a few shots of Remington 180 core lokt was getting us around 2500fps. This is fairly standard velocities for 180 grain factory ammo I believe out of a 22" barrel, no? The obvious question is if my scale was calibrated properly. I'm using an RCBS balance scale (one of the new ones out of the supreme kit) and I am certain I calibrated it. I'm pretty neurotic about it, as I would kind of like to keep my face.

I'm going to try and get a hold of Alliant. The more I'm talking with you guys, the more I'm glad I stopped at 48.5grains...

 

[RaySendero]

That resembles me!

I'm in the middle of stage of working-up reloads for my 30-06 using 180 Rem CLs.
Currently at 55.0 grs of IMR-4350 and have found this to be VERY accurate from my 20" barrel. Chrony says average of 2,540 fps - SD = 15.3, CV = 0.60% with XS of 40. I can detect some flattening of primer with magnifying glass. Yet no sticky bolt, no problem with extraction and no problem with pressure ring measurements.

 

[LifeAndLiberty]

OK, I called Alliant and I called Nosler. Here is a quick summary.

Alliant had some supplemental data that they haven't published yet for the 180 grain Partition with Reloder 17. COAL of 2.710 max charge 48.2 grains, gave them 2631fps in a 24" barrel. Nosler tells me they quote their seating depth at a 2.77 COAL but had no information on Reloder 17 in a 308 with that bullet.

I'm wondering if the guy from Alliant misread his seating depth as 2.71 instead of 2.77 (mistook the second 7 for a 1?) In either event, I was of the impression the further out I seated a bullet the less pressure I'd build (providing I was sufficiently off the lands) but the gentleman from Nosler equated the bullet being seated closer to the lands like a cork on a bottle. So, I'm guessing I'll have to go back to the drawing board and start around 44.5 grains as seat that Partition a little deeper than my 2.82.

Interesting to note, Alliant indicated their Reloder 17 (which gets a reputation for being sensitive to temperature) as being less temperature sensitive than Reloder 22, which a lot of people swear by in magnum rifles. I was steered to try RL23 and RL26 in those rifles, but again, no published load data that I can find...

 

[35 Whelen]

Alliants actual tested figures, sound spot on and are more than likely correct out of a 24" barrel that would be a warm load, to see the 2631fps. To hope to get there with a 20" barrel is going to be one heck of a streach, I have a buddy that shoots a Ruger redpad 77 in .308 and I just checked some old figures; When we loaded some 180gr Partitions; for him to go to Newfoundland Moose hunting, a few years back. His gun also has the 20" barrel, and we struggled to get 2500fps; out of his at the time, looks like it took 48. grs of W760 under the Nosler to get there. Good Luck with your testing :wink: ............................

 

[kraky1]

The argument about seating depth goes both ways even among the manufacturers. Hornady clearly states in their manuals that shorter seating depth equals less pressure and less velocity. their theory is the bullet gets a running start at the lands and the gases expand quicker. BERGER bullets on the other hand ...who has a very smart ballistician ....says the exact opposite ....they say the longer you seat the bullet the more internal case volume you have and the less pressure. And.... ive seen pressure tests where seating depth didn't hardly make a difference at all unless you are right on top of the Lands. Older Remington rifles had real generous magazines and pretty good throat areas....I've seen reduced speeds on the chronograph with those rifles as i hung a bullet out further from the case but in these rifle they still had a pretty good jump to the rifling.
Maybe the real answer here is every gun is a science unto itself and we all have to check it ourselves? Lol.

Today I got to the range with Hornady new eld - x 200 grainer in my Tikka 06. Hornadies 2 top powders recommended for this Bullet are superformance and re 17. The the superformance load was a dog... the full 100 FPS behind re 17. I had used a like load with 200 ab with re 17 before and the Hornady performed exactly like I thought it would and was a perfect match to Quick Load. Without touching quick loads parameters it thought the Load would do 2694 and my average was 2688. Ql was predicting 61 K pressure..... there were absolutely no pressure signs and I had 4 out of 5 at 1.2 inches at 200 yards but I had an unexplained 5th flyer. My notes on my reloading label said that I had inconsistent seating pressure and I had sized with a Lee collet die.... although I had a really tight ES of 11 FPS........ hard to find blame there! Definitely going to load up a larger number of those and try again. Going to give them a full length size this time.

 

[baltz526]

With two different 180gr Partitions in .30 I would load the protected point in the 308, for the shorter oal of the bullet.

 

[LifeAndLiberty]

With two different 180gr Partitions in .30 I would load the protected point in the 308, for the shorter oal of the bullet.

Is that because the shorter overall length will keep the bullet farther from the lands and possibly generate less pressure?

 

[baltz526]

With two different 180gr Partitions in .30 I would load the protected point in the 308, for the shorter oal of the bullet.

Is that because the shorter overall length will keep the bullet farther from the lands and possibly generate less pressure?

Or take up less case capacity