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Joined: Jun 2016
Posts: 99
Campfire Greenhorn
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Campfire Greenhorn
Joined: Jun 2016
Posts: 99 |
In round numbers, a grain of powder is about 2500 PSI in the 7x57. So Fotis' estimate is conservative. I never knew that, you learn something every day! Am I doing my math wrong or missing something though? if I'm using 47gr of powder and 1grain = 2500PSI. I'm looking at 47x2500=117500?
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Joined: Apr 2005
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Campfire 'Bwana
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Campfire 'Bwana
Joined: Apr 2005
Posts: 30,967 Likes: 5 |
In round numbers, a grain of powder is about 2500 PSI in the 7x57. So Fotis' estimate is conservative. I never knew that, you learn something every day! Am I doing my math wrong or missing something though? if I'm using 47gr of powder and 1grain = 2500PSI. I'm looking at 47x2500=117500? Doesn't work that way. What he's said was that if you are at 55,000 PSI and add 1 more grain of powder it will increase pressure by 2500 PSI
I got banned on another web site for a debate that happened on this site. That's a first
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Joined: Jun 2004
Posts: 11,116 Likes: 2
Campfire Outfitter
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Campfire Outfitter
Joined: Jun 2004
Posts: 11,116 Likes: 2 |
Yup. The change in pressure is pretty linear at near normal loads, but not over the full range of zero to full loads.
Be not weary in well doing.
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Joined: Jun 2016
Posts: 99
Campfire Greenhorn
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Campfire Greenhorn
Joined: Jun 2016
Posts: 99 |
Yup. The change in pressure is pretty linear at near normal loads, but not over the full range of zero to full loads. Oh I see, thanks for clearing that up. It's useful info
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Joined: Dec 2004
Posts: 2,325
Campfire Regular
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Campfire Regular
Joined: Dec 2004
Posts: 2,325 |
If i am loading an unknown or poorly documented cartridge / load combination, I find a load that achieves the desired velocity and appears safe ( bolt lift and primer condition, admittedly not very scientific) and shoots well, then I choose 5 cartridges to do a stress test with.
Load and shoot the same five cases at least five times. If the primer pockets are still tight, the load is producing safe pressures in that rifle.
I did that with a Brno 21h in 7x64. Worked up a load that was 3-4 grains of powder over the load data I had on hand, which was from USA sources. European data showed more promise, but with different powders. I chose a comparable burn rate powder, same weight bullet of similar construction. Things were looking OK. But to verify, I shot and loaded the same 5 cases 6 times. Primer pockets remained tight, accuracy and speed exceptional, and performance was better than I hoped. All good. Went on to shoot those same cases 10 times and they were still OK. So despite being "over book" I have full confidence that the load was certainly OK in my rifle.
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Joined: Jun 2016
Posts: 99
Campfire Greenhorn
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Campfire Greenhorn
Joined: Jun 2016
Posts: 99 |
If i am loading an unknown or poorly documented cartridge / load combination, I find a load that achieves the desired velocity and appears safe ( bolt lift and primer condition, admittedly not very scientific) and shoots well, then I choose 5 cartridges to do a stress test with.
Load and shoot the same five cases at least five times. If the primer pockets are still tight, the load is producing safe pressures in that rifle.
I did that with a Brno 21h in 7x64. Worked up a load that was 3-4 grains of powder over the load data I had on hand, which was from USA sources. European data showed more promise, but with different powders. I chose a comparable burn rate powder, same weight bullet of similar construction. Things were looking OK. But to verify, I shot and loaded the same 5 cases 6 times. Primer pockets remained tight, accuracy and speed exceptional, and performance was better than I hoped. All good. Went on to shoot those same cases 10 times and they were still OK. So despite being "over book" I have full confidence that the load was certainly OK in my rifle. Makes sense, I’m going to try that!
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Joined: Jan 2009
Posts: 1,222
Campfire Regular
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Campfire Regular
Joined: Jan 2009
Posts: 1,222 |
Incredible accuracy...great velocity...quit while you are ahead!
"That God could and would, if He were sought."
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Joined: Jun 2016
Posts: 99
Campfire Greenhorn
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Campfire Greenhorn
Joined: Jun 2016
Posts: 99 |
Incredible accuracy...great velocity...quit while you are ahead! I never intended to hot rod it, or try and get more velocity out of it. Just concerned that it was too hot of a load and that someday I may get a big surprise.
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Joined: Apr 2011
Posts: 15,334 Likes: 4
Campfire Ranger
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Campfire Ranger
Joined: Apr 2011
Posts: 15,334 Likes: 4 |
I'd be just fine with your load. Seems well within the norms for the cartridge and as long as your cases hold up along with accuracy on repeated firings I wouldn't worry about it a bit myself. 2850 with that LRX should be a great critter getter.
Semper Fi
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Joined: Dec 2008
Posts: 78,306 Likes: 2
Campfire Oracle
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Campfire Oracle
Joined: Dec 2008
Posts: 78,306 Likes: 2 |
"...the left considers you vermin, and they'll kill you given the chance..." Bristoe
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Joined: Apr 2011
Posts: 4,359
Campfire Tracker
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Campfire Tracker
Joined: Apr 2011
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First I've heard of using 7mm08 data. I'm loading for a cousin now and was having trouble grouping wise but got it worked out by loading a bit long for his push feed featherweight win 70. I used 7x57 data 140gr core lok, rem 9.5 and 40gr imr 4064. oal 3.074
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Joined: Sep 2009
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Campfire 'Bwana
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Campfire 'Bwana
Joined: Sep 2009
Posts: 46,261 Likes: 2 |
Yup, i shoot 48gr IMR-4350 under old school 175gr Speer Grand Slams and Partitions for 2700 fps, have shot that GS load since day one, no issues with 24" barreled '09 DWM 98 Mauser, even had 'Smith check for lug setback after 2-300 rounds, all GTG, RP brass is reloaded it's fourth time, i'll anneal, trim and load again when these are gone. 
Trump Won!
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Joined: May 2014
Posts: 10,458 Likes: 3
Campfire Outfitter
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Campfire Outfitter
Joined: May 2014
Posts: 10,458 Likes: 3 |
H414 is easier to find, because many are deleting from the inventory, I know I have. It's too temperature sensitive for this part of the country.
I prefer classic.
Semper Fi
I used to run with the hare. Now I'm envious of the tortoise and I do my own stunts but rarely intentionally
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Joined: May 2021
Posts: 3,511
Campfire Tracker
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Campfire Tracker
Joined: May 2021
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Most of the time the bolt lift was normal but on two occasions I thought; “mmm was that bolt a bit sticky just now or am I imagining it?”
Case head looks fine, to me.
Maybe I’m just being a sissy about it? But then I’d hate to have my rifle explode in my face too Doesn't sound fine to me....most likely wont explode in you face but it could eventially wreck your rifle. Myself I would stick with the loading manuals for the 7x57.
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Joined: Apr 2011
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Campfire Tracker
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Campfire Tracker
Joined: Apr 2011
Posts: 4,359 |
First I've heard of using 7mm08 data. I'm loading for a cousin now and was having trouble grouping wise but got it worked out by loading a bit long for his push feed featherweight win 70. I used 7x57 data 140gr core lok, rem 9.5 and 40gr imr 4064. oal 3.074 Thought I had it worked out but it wouldn't repeat the 1 group I got so switched to 50gr h4350 & nosler 140bt and they repeat great.
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Joined: Nov 2010
Posts: 578 Likes: 1
Campfire Regular
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Campfire Regular
Joined: Nov 2010
Posts: 578 Likes: 1 |
I loaded 139 gr Interlocks and 140 gr Partitions to 3000 FPS in a 22 in Ruger Tang safety M77 for years. 53 yrs of IMR4350 goes all the way into the neck of Winchester brass. I think your load is a little weak. 
Dyin' ain't much of a livin' boy - Josey Wales
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Joined: Jun 2005
Posts: 12,384 Likes: 1
Campfire Outfitter
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Campfire Outfitter
Joined: Jun 2005
Posts: 12,384 Likes: 1 |
Most of the time the bolt lift was normal but on two occasions I thought; “mmm was that bolt a bit sticky just now or am I imagining it?”
Case head looks fine, to me.
Maybe I’m just being a sissy about it? But then I’d hate to have my rifle explode in my face too Doesn't sound fine to me....most likely wont explode in you face but it could eventially wreck your rifle. Myself I would stick with the loading manuals for the 7x57. Maybe you should check the latest Speer manual on the 7x57. The latest Nosler has a few good loads as well. The problem with 7x57 data in most manuals and factory loads as well is there are too many old 93/95 Mausers and rolling block rifles still in use. SAAMI was cautious regarding pressure for the cartridge. Look at it this way. My Winchester M70 Featherweight also comes chambered in cartridges like the .270 and in 7-08 in the short action rifles. The 7x57 cartridge can hold more powder than the 7-08. So, it stands to reason that using 7-08 data in my 7x57 M70 is perfectly feasible. Due to the larger case pressure and velocity should/would be slightly less. I have three rifles chambered to the 7x57. Two, the M70 and Ruger #1 have no problem with 7-08 data. The custom Mauser does have problems even with the weak factory ammo at times which is puzzling as the rifle was originally a .270 Win. The only thing I can figure is the chamber is extremely tight. I'll probably take it back to the gunsmith who built the rifle and see if he can figure it out. Paul B.
Our forefathers did not politely protest the British.They did not vote them out of office, nor did they impeach the king,march on the capitol or ask permission for their rights. ----------------They just shot them.
MOLON LABE
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Joined: May 2021
Posts: 3,511
Campfire Tracker
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Campfire Tracker
Joined: May 2021
Posts: 3,511 |
I dont need to check the loading manuals I sold all my 7x57 guns years ago...no way I'm using 7mm 08 loading data in a 7x57.
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Joined: Jun 2004
Posts: 44,882 Likes: 9
Campfire 'Bwana
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Campfire 'Bwana
Joined: Jun 2004
Posts: 44,882 Likes: 9 |
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