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Discussion Starter · #1 · (Edited)
Hello, longtime lurker and first post.

Here is my situation. I am shooting a bolt action Savage 10 FCP in .308. It has around 1300 rds down the barrel. I've been loading both 168gr and 175gr Nosler CC bullets in LC LR cases with 42gr of IMR4064 with a CCI200 primer. Initially, this load gave outstanding accuracy with no indications of pressure.

Now, I'm getting some difficult bolt lift at the top right before it unlocks. It's also gained about 50fps when the temperature is 30 degrees cooler. Factory Federal GMM is now showing ejector marks on the case head when fired in the rifle when previously it was fine. The FGMM is from the same box. LC M80 ball fires and extracts without issue. I've also fired Winchester and Hornady factory ammo without issue.

I thought it was an issue with my loads, but with the FGMM showing pressure signs, now I'm not sure.

I'm using a Lee FL sizing die. I've also tried a RCBS small base die. I've tried annealing and also without annealing. None of these have seemed to have any effect.

I tried downloading to 41.5, but it didn't alleviate the problem either. With 42gr I get sooty case necks and with 41.5 the shoulder gets some soot.

I measured the case capacity and it averages 55.4gr of water.

Any help would be appreciated.
 

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I've got a Savage 10-series as well... it does very well with the 168grn Nosler and IMR4064, too.

Question for you: Has the accuracy or POI changed since you've started seeing pressure signs?
 

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What is your velocity? Is it another lot of powder? Crimp or no crimp.

I have a savage fple2b in .308. Mine has a tight chamber and is finniky about what reloads fit. But I have never had pressure or signs of pressure problems I use 41gr h4895 and 168gr Amax oal 2.8. no crimp.
 

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Discussion Starter · #4 ·
The POI and accuracy haven't changed. I vetted this load by ladder test and ES/SD numbers on my LabRadar. I still want to use it, but I'm a bit apprehensive now.

One variable that changed is the case lube. I began by using Dillon case lube and when that ran out I switched to Frankfort Arsenal spray lube. I tumble after sizing for an hour or so in walnut and the cases don't feel slick. Don't know if that is a factor or not.
 

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how many loads on your brass? also what kind of brass?

sounds like its time to anneal... never mind. I just reread your post. have you tried to bump your shoulder back?
 

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Discussion Starter · #6 ·
What is your velocity? Is it another lot of powder? Crimp or no crimp.

I have a savage fple2b in .308. Mine has a tight chamber and is finniky about what reloads fit. But I have never had pressure or signs of pressure problems I use 41gr h4895 and 168gr Amax oal 2.8. no crimp.
Velocity was avg 2625 @ 60 degrees. When the temp dropped to 20 the velocity raised to 2680. I have used the Lee FCD on some of the loads and strangely these don't seem to stick as much, although they still do the majority of the time.

Powder is from the same 8lb jug and primers are out of the 5,000 case.

I clean the rifle with brush/patches and MPro7 after range trips and use Sweets every 500rds or so.
 

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My guess based on the Federal GMM showing signs too is the headspace has changed. Do you have a tool to check it? How clean is your chamber?
 
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Discussion Starter · #8 ·
how many loads on your brass? also what kind of brass?

sounds like its time to anneal... never mind. I just reread your post. have you tried to bump your shoulder back?
There's a max of 4 loads on the brass. It's Lake City LR.

I full length size the brass and using a Hornady gauge it shows the shoulder moving back .006".
 

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Discussion Starter · #12 ·
What is your velocity? Is it another lot of powder? Crimp or no crimp.

I have a savage fple2b in .308. Mine has a tight chamber and is finniky about what reloads fit. But I have never had pressure or signs of pressure problems I use 41gr h4895 and 168gr Amax oal 2.8. no crimp.
The avg velocity was 2625 when the temps were in the low 60s. Temps dropped to 20 over the past few days and the velocity was 2680. It isn't making sense to me.
 

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I would have to see it in person but my guess is that your chrono isn't reading right and the bolt lift/ejector marks are entirely subjective.

In other words everything is most likely fine.
 

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Discussion Starter · #14 ·
I would have to see it in person but my guess is that your chrono isn't reading right and the bolt lift/ejector marks are entirely subjective.

In other words everything is most likely fine.
It is entirely possible the chrono isn't giving accurate readings due to the cold and electronics. However the bolt lift and ejector marks are not normal.

The mark from the ejector leaves brass sitting proud of the case head and a well defined shiny spot. Brass shavings are also present on the bolt face.

The bolt sticks just before unlocking and I've had to smack the bolt knob hard with my palm numerous times to get it to pop open. It's one step away from needing a mallet. It also has an extended bolt handle with plenty of leverage.
 

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It is entirely possible the chrono isn't giving accurate readings to to the cold and electronics. However the bolt lift and ejector marks are not normal.

The mark from the ejector leaves brass sitting proud of the case head and a well defined shiny spot. Brass shavings are also present on the bolt face.

The bolt sticks just before unlocking and I've had to smack the bolt knob hard with my palm numerous times to get it to pop open. It's one step away from needing a mallet. It also has an extended bolt handle with plenty of leverage.
I've got a long bolt handle as well... if you are having to fight it, something is wrong. Here's my though... something with your load has changed. The higher velocity in colder weather is one of the keys... it sounds like you are up a grain of powder or something. I think my last loads with 168/IMR4064 were @ 42grn and I did not have any pressure signs, the primer was still rounded at the edges, but that is with commercial RP brass and no crimp. I would suggest you really look at your reloading process...

What are you using to measure your powder charges?
 

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Discussion Starter · #16 ·
I've got a long bolt handle as well... if you are having to fight it, something is wrong. Here's my though... something with your load has changed. The higher velocity in colder weather is one of the keys... it sounds like you are up a grain of powder or something. I think my last loads with 168/IMR4064 were @ 42grn and I did not have any pressure signs, the primer was still rounded at the edges, but that is with commercial RP brass and no crimp. I would suggest you really look at your reloading process...

What are you using to measure your powder charges?
I'm weighing on a RCBS beam scale. Not sure of the model, but I think 5-0-5. I trickle all the charges. I had something similar happen with some PPU brass a couple years ago and never figured that one out. I only had 50 of those cases and tossed them. I've got two 5 gallon buckets of the LC LR brass so I'd kinda like to solve this.

I've been researching this for a week or so now and Google searches reveal several hits with similar questions, but no resolution as far as I have read.
 

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Discussion Starter · #18 ·
For clarification, the ejector marks were on the Federal brass and not the Lake City.

There aren't any pressure signs per se on the LC brass. It's just the bolt lift. It seems normal up until the point it begins to recock the striker. During dry fire testing nothing seems out of the ordinary.
 

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Any sign of case separation? That would be a big clue to a headspace issue which really seems unlikely. More likely is a load chain issue. Double check your scale for accuracy or try another scale to compare. The FGGM thing is curious, but its not impossible for it to have some variation too. Its not hard to make boo boos on the bench. I found myself yesterday loading 175 gr SMK bullets when I thought I was loading 168's! Had to pull a whole box and start over. I have also once or twice used a different primer than intended. Switching cases can cause issues. Lots of ways to mess things up. If all else checks out OK it might be time for a visit to the 'smithy.

You might also try slapping a little lube on your locking lugs. Dry lugs will be grabby.
 

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Discussion Starter · #20 ·
Could the once fired LR brass been some how shot out of a machine gun?

Check the diameter of the once fired brass near the base.
Definitely not fired out of a belt fed. I was present while all of it was fired.

With my calipers I checked 20 cases at random before they were resized. They measured .468-.470".
 
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