M96 6.5x55 problem with 160 grain loads

[BenKK]

Got a beautiful M96 6.5x55 from 1900. It got shortened to a carbine some decades later, if I understand correctly. It looks to be in very good condition.

It shot 140 grain PPU factory ammo nicely, just a bit high.

I really want to shoot Woodleigh 160 grain PPSNs. So I loaded some using the Woodleigh Manual starting load of 40 grains of 2209. I used new Norma brass.

I had three shots this morning. The first one I wondered if the primer appeared slightly flat. The second one seemed a little stiff to open. The third one required a plastic mallet to lift the bolt, and the primer had popped out.

Accuracy was okay at 25m, an improvement on the factory 140s.

I looked in my two Nick Harvey manuals - no 2209 data. ADI online lists an identical starting load to what Woodleigh do for 2209.

Any advice?

To complicate the mystery, when I resized the PPU brass last week, I noticed the Lee die left a ring stamped into the brass at the base of the shoulder, and the dummy I made was a little stiff when closing the bolt. I have an RCBS die inbound to see if it’s a die problem.

 

[sestoppelman]

Hard bolt lift usually means one thing. Excessive pressure. Try backing off a couple grains and try it. Not familiar with 2209 powder.
The ring from the dies is no big deal, assume its not deep.
Its OK to feel a little pressure on bolt closing, but not too much, is brass too long? That can cause pressure spikes by creating a pinch at the neck of the chamber.
Starting load in one gun can be max in another.

 

[Wyatt Smith]

The pressure when you push the bolt down could be the bullet hitting the lands. That could cause a pressure spike if it doesn’t have any jump.

 

[BenKK]

Thank you, gents. To clarify, there’s no extra pressure closing the bolt on either the factory ammo or my handloads in brand-new Norma brass - only on the resized brass that’s once-fired (possibly an issue with the Lee die?).

 

[sestoppelman]

Probably not the die, but the setting you have it at. Turn it down a little bit at a time and keep trying the brass until it closes more easily.

 

[shootist~]

Possibly a sizer die problem.

I have seen pressure signs with brass that was not sized down enough.
Also from factory ammo on the high side of normal (shoulder setback) in a chamber that was (and is) on the tight side.

The other possible (my SWAG) is the Swede has excessive headspace . Do you have access to a No Go or Field headspace guage?

Another very handy and inexpensive tool to have is the Hornady Cartridge Headspace Tool.

 

[sestoppelman]

If excess headspace was the problem he probably wouldn't have tight rounds.. Anything is possible but a die problem is probably the least likely. That's why I advised earlier to screw the die down a little farther and look for an easier fit.

 

[shootist~]

PPU Brass as the culprit?

A young guy at the range recently was having the exact same problem with PUP brass in a 308W. His identical load in Lapua brass was working well, (easy bolt lift). I also suspected he had bullets jammed into the lands, however.

 

[BenKK]

Sorry All, I have rambled and haven’t been clear. I will try to be succinct:

1. PPU factory ammo shot and cycled perfectly.

2. After resizing the PPU there was a weird ring imprinted into the base of the shoulder. A dummy round made with this resized PPU was snug and required a little extra pressure to close the bolt handle.

3. I loaded brand-new Norma brass (without resizing) with 160 grain Woodleighs and they fed perfectly - but I ran into pressure problems (blown primer, difficult bolt lift).

 

[shootist~]

My thoughts were if the brass is getting blown so far out of spec, the shoulder is getting damaged or crushed (that "ring"), on resizing. Not saying thats a high probability.

I have a couple of M96 Swedes, (one is an M41b), a 1907 M96/38 carbine and a M94 Calvary Carbine. One or two will close on a NO-GO gauge and the others will partially close. I think it's a good idea to know how they headspace, and to set up the sizer die accordingly.

If excess headspace was the problem he probably wouldn't have tight rounds.. Anything is possible but a die problem is probably the least likely. That's why I advised earlier to screw the die down a little farther and look for an easier fit.

 

[shootist~]

If you are at the minimum starting load and getting blown primers, it is indeed a mystery. Sorry that I jumped in without understanding the issue.

I can only suggest double checking the obvious:
Weigh a sample of the bullets and also verify their diameter.
Verify that your powder scales are properly zeroed, calibrated, and finally, that you did not accidently drop the wrong powder charge.

 

[Tim Blackwell]

Ben, have you tried loading the once fired Norma brass again and seeing how it fares? I'm thinking that maybe with the virgin brass you are encountering 'minimum brass, large chamber' issues. Which may well disappear once fire formed (with minimal resizing as required).

 

[Shootist43]

BenKK , as you know I use a 6.5 x 55 Swede quite a bit. I just ran your recipe through QuickLoad assuming a 24" barrel. Using a Woodleigh 160 Gr PP and 40 Gr. of 2209 the resultant pressure is just over 40,000 Lbs. vs a P-Max pressure of over 55,000 Lbs. I think you can rule out the load being an issue. As others have said check your scale, OAL, head spacing etc. With good brass and cartridge dimensions QL "suggests" a max load of 44.5 Gr. of 2209.

Another thought, have you double checked the powder type? I.e, 2208 could cause these issues.

 

[Mike Van Horn]

I am very interested to see what is found in this thread
I am having the same issue with a 28 Nosler in a Nosler rifle
Reloading:
162 ELD-X, min - max no problem
165 game changer, min-max no problem
168 LRX using the online Barnes manual starting load, first shot a little hot, second the same, third blown primer and had to let the gun cool to get the action open.
Group at 100 was one ragged hole
Have a friend that is a competition shooter come over, he checked everything he could think of, size of neck in the chamber, neck tension on the bullet, thickness of the brass at the neck, shoulder set back at sizing, OAL of loaded round.
We found nothing. Using Hornady and ADG brass, same results.
Going to try different powder, maybe just the chamber, brass, bullet, powder, primer combo isn't working together?
Never seen this in 30 some years of reloading

 

[BenKK]

Still no good.

Pulled those 40 grain loads and backed a few down to 35 grains.

First I merrily fired-off five PPU factory 140 grain bullets, just to make sure it was good. It was fine - accurate and easy to cycle.

Then I loaded a single 35 grain 2209 / 160 grain Woodleigh PPSN and the bolt jammed rock-solid. Had to go home and open it with a hammer. The primer had popped.

I think I’ll send it to a gunsmith when things open up again.

It’s frustrating.

 

[sestoppelman]

The primer in that picture looks punctured. Is it? Did you use the same primer in all the loads?

 

[BenKK]

The primer in that picture looks punctured. Is it? Did you use the same primer in all the loads?

Sir, you are absolutely correct. I hadn’t noticed this. I’ve been using the same primers in my loads.

Why would it puncture one primer and not the other (factory PPU)?

 

[shootist~]

Have you verified the diameter of the 160s as well as their weights? Not likely, but just to be sure you weren't sold 7mm or out of spec bullets by accident.

 

[sestoppelman]

Sir, you are absolutely correct. I hadn’t noticed this. I’ve been using the same primers in my loads.

View attachment 341536

View attachment 341537

Why would it puncture one primer and not the other (factory PPU)?

Primers are not created equal, some have harder shells than others. Here CCI seem to have a harder shell than say a Winchester or Federal.

 

[BenKK]

Have you verified the diameter of the 160s as well as their weights? Not likely, but just to be sure you weren't sold 7mm or out of spec bullets by accident.

They’re definitely 160 grains on the scales.

The battery in my calliper is dead, and it’s going to be hard to get another (but I’ll make a plan). However, I pulled a PPU projectile and clamped the calliper on tight. Then I pulled it out of the calliper and pushed a Woodleigh in, which was difficult (thus showing a very slight increase in diameter - but I need to confirm this).