Unseated fired primers on reloaded .35 Rem ammo?

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cantgrowup
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Unseated fired primers on reloaded .35 Rem ammo?

Post by cantgrowup »

I've experience some partially unseated primers on some reloaded .35 Rem ammo that I reloaded and fired myself in two different Model 8 rifles. The loads themselves are in the middle of the recommended ranges from the Hornady Reloading Manual No. 11 with 32.0 gr of H4895 pushing a Hornady 200gr RN Interlock bullet at 1800 /- fps. Out of 50 rounds, the primers were above flush in about 20-25% of the fired cases. The cases have only been reloaded twice and I don't suspect enlarged primer pockets, but in any case I wouldn't expect the primers to be pushed back against the bolt face if the case were fully seated until the moment of ejection and pressures were fully dissipated prior to extraction from the chamber . I'm still not fully understanding of the recoil operation of the Model 8 rifles and was wondering if there was something that could be allowing pressures to partially unseat a primer prior to extraction and ejection of the fired case.

Has anyone else ever witnessed something like this with the Rem 8/81?
Rifleman
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Re: Unseated fired primers on reloaded .35 Rem ammo?

Post by Rifleman »

I haven't in a Rem 8/81, but I did so in a WW 2 British Enfield .303 British rifle. I noticed a number of the primers in my reloads were not flush or a bit above the line. They were from some reloads early in my reloading for the rifle and I was way on the lower end if not the bottom of the load chart for powder grains. I've read and heard of firearms that didn't have enough pressure generated after firing to force the case head back into the bolt or recoil shield to reseat the primer into the primer pocket. I upped the powder weight and no more problems. I've heard of this in a number of calibers/actions, but as you pointed out your reloads are in the middle range for a 35 Remington using H4895 and the 200 grain bullet. Can't say there, unless your particular combo in your Model 8 needs a bit more powder for more pressure. How was the ejection and working of the action? Did it appear that your ammo had enough 'umpppth' to sufficiently work the Model 8, cycling it as it should? Semi-autos are finicky breeds sometimes requiring special diets. I noticed that the loads in the Hornady (#10 manual) were tested using a Marlin 336 Lever action rifle. May have been fine for a manually operated rifle, but in your semi-auto Model 8 just didn't have enough what it took to operate the action. I wouldn't increase the powder with H4895 until you can check out other manuals, reloading charts, and such with the 4895, hopefully may find info on others using your H4895 and 200 grainers.

Also I've heard of varying case length playing games with pressure. You mentioned the cases had been loaded twice before. Were they from your loadings or did you get them from someone. Saying this as wondering if your cases were all or nearly uniform in length within .002" or so. Just a thought. From all I've read and heard a semi-auto is more finicky about uniform case length and of course the resulting COL. Cases may need trimming. Another thought, when you seated the primers, did they all require about the same pressure to seat (assuming you were using a hand primer). A progressive unit wouldn't really tell you IMO. Early in my reloading days I had some 38 Special cases once that had been reloaded a number of times (lots) (they were given to me by another shooter). When I seated the primers I noticed some almost fell into the primer pocket, being cheap, I loaded them anyway and had around 33% problems with them. Lesson learned. Just some thoughts. Your Hornady manual, wouldn't that have been a #10, I checked and they haven't come out with a #11 from what I've seen. Just came out with #10 several years ago. Just my thoughts!!!
cantgrowup
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Re: Unseated fired primers on reloaded .35 Rem ammo?

Post by cantgrowup »

You are right about the most recent Hornady reloading manual being #10. I was going off of memory. And you are probably right about the mid - range load being too light to force the case back against the bolt face. The brass is new mfg Hornady and below the max length allowed. The gun cycles fine with these loads so I probably won't increase them much (if at all) to keep wear and tear on the old gun to a minimum. I just never experienced moving primers with any of my other semiauto guns.
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Wildgoose
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Re: Unseated fired primers on reloaded .35 Rem ammo?

Post by Wildgoose »

I have an M8 in 35 made in the 30s and experienced the same issue with reloads. I came across an article that noted in the case of the Rem. 35 that over the years the amount of set back on the shoulder was slightly changed from the early days. So with a later manufacture dies the shoulder was set back a little more resulting in primers backing out on firing in the older rifle. I purchased a vintage Lyman die set on line and the reloads using these did not have the primer issue. Upon care full examination the shoulders were indeed not set back as far as with the newer die. The difference was very slight but apparently enough to solve the issue.
Rifleman
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Re: Unseated fired primers on reloaded .35 Rem ammo?

Post by Rifleman »

Interesting Wildgoose. Do you recall where you read that?
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Phyrbird
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Re: Unseated fired primers on reloaded .35 Rem ammo?

Post by Phyrbird »

This thread is a Really good reason to have a method for measuring headspace/shoulder of our fired rounds. I found the Hornady gauge for this is a great help. The first device I have found to test this reliably. Cheap insurance!! I also noticed on some cases the diameter of the collars are very close to the SAAMI datum diameters used.
I have found some unusual data from early rifles that could bear watching. Now I'm forewarned I'll be paying closer attention.
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Fred
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Re: Unseated fired primers on reloaded .35 Rem ammo?

Post by Fred »

Here are 5 different 35 rem rounds from two different barrel/bolt combinations in an M81.
These are factory 200gr core-locts so probably pretty mild on the pressure.
I bet the headspacing's a bit different between the barrels. You can see that the ones in the rear have proud primers after firing, likely from a looser (deeper) chamber than the other.

If you're re-loading the spent casings, then you probably only have to neck-size them. The pressure's likely not high enough to really stretch anything out of spec besides the neck.

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cantgrowup
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Re: Unseated fired primers on reloaded .35 Rem ammo?

Post by cantgrowup »

Yes... I need to measure the headspace with my Hornady kit, and keep the brass specific to each .35 Rem rifle. I will then just neck size to see if that helps move the shoulders up to where there is no excessive headspace.
Ki6vsm
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Re: Unseated fired primers on reloaded .35 Rem ammo?

Post by Ki6vsm »

A little late to this party, but I figure I may as well add what I have, info wise. I recently fired my Model 8 (.35 Rem) for the first time. I put 25 rounds of factory loaded, new Remington ammo through it. I noticed this same issue. About 25% of my cases have raised primers to one degree or the other.

Not the best pic, but you can get the idea.
35RemFactoryAmmo.JPG
35RemFactoryAmmo.JPG (64.31 KiB) Viewed 10617 times
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