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Joined: Mar 2005
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Campfire Ranger
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Campfire Ranger
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John,
You are correct. I was thinking of the 150g Corelokt. I have the Remington brochures in that period, and it was the 150g that was reduced in the late 70’s and again in the early 80’s.
Casey
Not being married to any particular political party sure makes it a lot easier to look at the world more objectively...
Having said that, MAGA.
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One load tested in one rifle. Both of uncertain history. No question about the rifle?
I'd look forward to seeing results with new handloads. How do velocities stack up with book charge values?
You might consider shelving your 30 remaining cartridges for later study.
Ken
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Joined: Nov 2013
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Campfire Ranger
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Campfire Ranger
Joined: Nov 2013
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Maybe some of that pesky chemical bonding is involved? Pull ‘em, for certain.
I once bought 100 rounds of Wolf “Match” .308. Only fired a couple as I ran into hard lift as you described with a Kimber Longmaster. They reimbursed me fully without question, so they either knew they had an issue, or were just being very cautious.
What fresh Hell is this?
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Campfire Regular
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OP
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One load tested in one rifle. Both of uncertain history. No question about the rifle?
I'd look forward to seeing results with new handloads. How do velocities stack up with book charge values?
You might consider shelving your 30 remaining cartridges for later study.
Ken Good point I will go buy one box of Federal 7mm ammo and try that. I usually only shoot my own reloads but typically buy a box of factory with a new or "new to me" rifle. I'll also measure the OAL, i wonder if the bullet is jammed against the lands in the factory ammo. I don't think it's the rifle because of the velocities I'm getting and it's shooting close to .5 MOA. Too bad about the pressure, 3000 fps with a 175g bullet and sub MOA could've talked me out of reloading for this rifle!
Regards,
Chuck
"There's a saying in prize fighting, everyone's got a plan until they get hit"
Ghost And The Darkness
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Joined: Feb 2005
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I have had pressure signs with more than a few boxes of Weatherby ammo.
Last edited by BWalker; 04/08/24.
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Hey, colorado Reloader 23 is your friend if you can find any. Other than that stock up on Ramshot Magnum.
41
We deal in lead, friend.
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Have written about this before, but here goes:
The 7mm Remington Magnum was introduced in 1962. The original advertised muzzle velocity for the 175-grain factory load was 3020 fps.
During the next decade or so, the Sporting Arms and Ammunition Manufacturers Institute (SAAMI) moved away from the copper-crusher pressure-testing equipment that had been standard to piezo-electronic testing--which was more sensitive. It was discovered that the 7mm Remington Magnum often exhibited wider variations in pressure, both high and low, than many other cartridges, and since SAAMI was concerned with the higher-pressure variations, they reduced the Maximum Average Pressure (MAP) somewhat.
This resulted in the standard listed muzzle velocity of 175-grain ammo being reduced to 2860 fps. At that time SAAMI used 26" barrels for most rifle testing, but since most factory 7mm Remington Magnums have 24" barrels velocity was somewhat less.
(Every time this general subject comes up, several people comment that they've never "noticed" wider variations in pressure in 7mm Remington Magnums. But every pressure-lab I've ever visited, whether in a bullet/powder company or an ammo factory, has documented it, especially with certain bullet powder combinations.) The SAAMI spec throat for the 7mm Rem Mag is very poorly done. Remington (old) did not cut SAAMI spec throats in either the 7mm Rem Mag or another SAAMI problem child the .243 Win. I assume Mike Walker was the guy who fixed the factory Remington chambers for those cartridges. SAMMI spec chambers (short freebore with abrupt leades) used for pressure testing are going to show the issues of such poor throat design. The OP's ammo is hot because even in a decent freebore/leade throat 3000fps with a 175gr bullets is pushing on the yield strenght of brass. Probably safe enough to shoot but Remington brass is not the hardest of brass. One load tested in one rifle. Both of uncertain history. No question about the rifle?
I'd look forward to seeing results with new handloads. How do velocities stack up with book charge values?
You might consider shelving your 30 remaining cartridges for later study.
Ken Good to see you post, Ken.
Last edited by JohnBurns; 04/08/24.
John Burns
I have all the sources.
They can't stop the signal.
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Campfire Kahuna
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John,
Yep, have encountered all that in many factory rifles in both 7mm PM and .243 Winchester. In fact was told by the head of the ballistic-testing department at one of the MAJOR ammuntion companies during a 2-day visit of their facilities that the .243 has also long been a major problem-child....
John
“Montana seems to me to be what a small boy would think Texas is like from hearing Texans.”
John Steinbeck
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I bought 10 boxes of Norma 340 Wby ammo. Loaded with 250 grain Woodleigh roundnose bullets. 3210 fos avg from my 340. Bolt opens with 2 fingers. Rifle is a Sako Finnbear with Bofors barrel; 12 groove.
Crazy stuff happens
NRA Benefactor Member
Those who live by the sword get shot by those who don't.
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Thanks for all of the advice. I'm coming to the conclusion that the bullets are seated out too far for my rifle and are jammed against the lands. I will put this to the test at the range. I plan to blacken with soot one of the bullets and chamber it to see if that's the case. I also plan to seat the bullets in about 10 rounds 1/10" deeper.
Regards,
Chuck
"There's a saying in prize fighting, everyone's got a plan until they get hit"
Ghost And The Darkness
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Just use a felt tip marker. I would be a little leery of smoking a loaded round. 🔥
NRA Life,Endowment,Patron or Benefactor since '72.
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Regards,
Chuck
"There's a saying in prize fighting, everyone's got a plan until they get hit"
Ghost And The Darkness
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I'll make it to the range this week. I'm pretty sure the factory ammo is seated out too far and is jammed againt the lands. If that's the case, I'll seat them all 1/10" deeper.
Regards,
Chuck
"There's a saying in prize fighting, everyone's got a plan until they get hit"
Ghost And The Darkness
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