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220yotekiller

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I was helping my friend who is new to reloading today. We were loading for his 7mm Rem Mag. He had a bunch of 150 gr Hornady CX in front of 64 gr of H4831 (the minimum was 62gr and the maximum was 68gr according to Hodgdon). He didn't have any brass so I gave him some once fired Hornady that came with a bunch of federal that I bought. We loaded them 10, 30, and 60 thousanths of an inch off the lands, all of the OALs were within a thosandth. Then we went to the range, lets just say it wasn't pretty, he fired the first shot and couldn't get the bolt open. I had to hit it with the palm of my hand to get it to open, I was thinking that we had a pressure spike but the brass had NO signs of pressure at all so thinking that it might be a fluke we loaded another. The same thing happened. I looked at the brass in the sunlight and the only thing off that I could see was just ahead of the belt you could see where it had been stuck, it wasn't bulged, it was just stuck. Anyone had this happen before?
 
I take it the cases were full length sized?

Was the bolt hard to close to begin with?

Did you try putting a sized, unloaded case in the chamber?

If all the above check out, it sounds like you were over pressured.

It's called a start load for a reason.

Since it's a mono bullet, you might want to compare load data with Barnes instead of Hodgdon.
 
I take it the cases were full length sized?

Was the bolt hard to close to begin with?

Did you try putting a sized, unloaded case in the chamber?

If all the above check out, it sounds like you were over pressured.

It's called a start load for a reason.

Since it's a mono bullet, you might want to compare load data with Barnes instead of Hodgdon.
They were full length sized. We were using Hogdons data for the 150gr Barns ttsx. The bolt was shutting a touch stiff but nothing that i havn't seen before. I ran several through my action and they ran fine. I have a Rem 700, he has a Browning A bolt.
 
Sounds like possibly a probem with his rifle if same reloads are shooting fine in your gun. Mono bullets are longer per weight compared to lead but 150 gr is rather light for 7mm magnum so I wouldn't think length should be an issue. Be interested to see how this unfolds. Only a few times have reloads stuck in my Springfield's chamber after firing and always bad brass.

Did you trim the brass? Yes, I see you checked length
 
You do know "Barnes" bullets can't be close to the lands.
They need a "Jump"
Check the Barnes information for the right space.
0.050" is Barnes starting recommendation. I have gone from .035" to 0.075" tuning various rounds (and fitting magazines) with no real change in pressure signals, but never went less than .035".
 
I ran into something similar years ago on a Kleingunther (KDF) 7mmRM rifle belonging to a buddy. It is essentially an A-Bolt action. We ended up having to have his chamber re-reamed because the neck area was too short for 2.900" brass. My Forster chamber gages couldn't find that since they have a shoulder but no neck.
 
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I personally am cautious about using data intended for barnes bullets on any other monos. With all of the groves they seem to have less engraving pressure.

That said if you haven't already try some factory loads
 
I have bought "once fired brass" during the big shortage that had obviously been fired in a rifle with an oversized chamber and was expanded beyond the normal dimensions near the head of the base.

Even after full sizing it was difficult to even chamber, and extraction was very hard. There were clear rub marks near the case head after they had been chambered in a normal chamber. I tried those cases in three different rifles with the same result. The only solution was to discard those cases. Buyer beware.

Your situation sounds identical to mine.
 
Sounds like a pressure problem to me too. I use different books for different brand bullet's but always start low and work up. Surprised there were no pressure signs on the case's. Only thing I would know to do with it is take it to a gunsmith and have the chamber checked out.
 
0.050" is Barnes starting recommendation. I have gone from .035" to 0.075" tuning various rounds (and fitting magazines) with no real change in pressure signals, but never went less than .035".
We were useing 150gr Hornady CX so we used the Barnes 150gr data.
 
Measure a fired case against a sized case of the same batch you were shooting. Check base to shoulder dimension-preferably off the datum line of the shoulder. Check neck diameter, shoulder diameter, and diameter in front of the belt. If there are marks on the cases from being stuck the chamber may need polished.

Has he had the same issue with other ammo?
 
I just took a peak at my Hornady manual, shows 150 GMX max for H4831 SC to be only 62.8 grains. It doesn't list H4831 in the 11th edition of that manual but I would guess it would be about the same maximum.
 
Measure a fired case against a sized case of the same batch you were shooting. Check base to shoulder dimension-preferably off the datum line of the shoulder. Check neck diameter, shoulder diameter, and diameter in front of the belt. If there are marks on the cases from being stuck the chamber may need polished.

Has he had the same issue with other ammo?
No, it a great shooter with Federal premium ammo.
 
The problem is most likely because the fired brass isn’t being resized all the way due to it being a belted case. The case was fired in a different chamber and it’s probably a little larger than his also.
Take a resized case and sharpie above the belt and the shoulder and then chamber it in your buddies gun and see if it’s making contact anywhere.

Larry Willis makes a special die for fully sizing belted cases and I’d recommend it for anyone trying to use brass fired in another rifle.
 
I just took a peak at my Hornady manual, shows 150 GMX max for H4831 SC to be only 62.8 grains. It doesn't list H4831 in the 11th edition of that manual but I would guess it would be about the same maximum.
It's been reported here before that bullets of identical weight from different makers can have varying pressures, but IIRC one of them was Sierra. You indicated that there were no obvious pressure signs like flattened primers or ejector marks on the case head. Sounds like a tight spot in the rifle's chamber.
 
I was helping my friend who is new to reloading today. We were loading for his 7mm Rem Mag. He had a bunch of 150 gr Hornady CX in front of 64 gr of H4831 (the minimum was 62gr and the maximum was 68gr according to Hodgdon).

I just took a peak at my Hornady manual, shows 150 GMX max for H4831 SC to be only 62.8 grains. It doesn't list H4831 in the 11th edition of that manual but I would guess it would be about the same maximum.

Since hornady suggests using its GMX data it would appear that you are 2 grains over hornadys suggested max load.
A really stiff bolt is a significant sign of over pressure.
What am I missing?
 
If your using one company's data wwith someone elses bullet's no sweat. Start low and work up. What I would not do is cross like that using mono bullet data with lead core bullet's or lead core data with mono bullet's. Not a clue how a solid mono bullet bullet would do with lead core data and never willing to chance a lot.
 

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