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While working up loads for my 1895G Marlin,(.45-70) I noticed a difinite ring developing on the new Starline brass I was using. I started at 90% of max load of 68 gr. of H335 (61.2 gr,) for a 300 gr. JHP. No indication of high pressure there, but at 63.5 gr.of H335 a ring started to form. This occurred for all loads, 300 gr. JHP, 350 gr. JFP, and 405 gr. JFP.at about .933% of the listed max loads for Marlin Lever Actions. I can't estimate the pressures involved but the velocities were about 2085 fps for the 300 gr., 1915 fps for the 350gr, and 1787 fps for the 405's. The ring, of course, got more pronounced when the load was increased to .945-.955% of max. What puzzle's me is this: There was no expansion of the brass at the case head or web, but only up about .260" from the rim where the brass should be supported by the chamber. Do Marlin 1895G's have an oversized chamber? Why no expansion closer to the rim before the webbing where the case is not supported. Also, would the cases with the slight ring be safe to reload with reduced loads, something the equals factory loads. Hope somebody has experienced the same thing and has a satisfactory answer. Thanks in advance, dgang
 

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dgang,

If I understand you correctly, what is happening is the case is expanding on what some call the "pressure ring". This is not necessarily a sign of excessive pressure but more of an indication of the thinner area of the case expanding to seal off the chamber. You may also notice that the "ring" is not evenly formed around the entire circumference of the case. Through a series of reloadings they will form to a consistant ring around the case depending on how much your sizing die forms this area of the case back.

The head and web of the case is much heavier of course and typically will not expand to the degree that the thinner case wall areas will.

It is possible that your chamber is on the larger end of tolerances but that's not really a concern.

If you purchase factory loads with the same brand of case you can get an idea of expansion in this area as a ballpark idea of the pressures you are running with your handloads.

If you find after a relatively few reloadings that your primer pockets are feeling noticably looser when seating new primers, it's usually a good indication that you are exceeding the elasticity of the brass and opening up the heads of your cases and should back your loads down some.

Sorry to be a little obscure with a definate answer but without a fully equipped pressure gun, it's anybody's guess what your pressures are in your loads.

Regards
 

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dgang,

Back when the 1895(new Model) first came out, I did a pretty fair amount of hot loading for this rifle and calibre. I pretty much used 3031 and 400 gr. Speer bullets exclusively. I too ran into the bright ring that you talked about. Starting at 48gr. 3031 the case was normal and recoil brisk. Increasing the charge in one grain increments saw nothing unusual until the 53 grain charge. At this charge there started to appear a ring back near the vicinity of the case web! The ring became brighter and more pronounced the heavier the charge from 53 gr. on up. I shot charge weights all the way to 55 grains, which is about all the compressed charge that the case will handle. I called Speer`s customer support and had a good 30 minute conversation concerning this ring! The svc. rep agreed that 55 gr. 3031 was the absolute limit, both in terms of capacity and pressure. Probably about 40,000- 50,000 psi. He felt and I concurr that the ring was caused by the small amount of action stretch that Marlin`s have at lock up. Below a certain pressure, about 52 gr. or 28,000-32,000 psi, there was no action stretch and hence no ring, above that figure the ring became more pronounced the higher the pressure. His opinion was that the ring was a stretch ring, caused by the action taking a small set at ignition! The ring did not bulge, and the case fell out of the chamber after firing. It has been said that these Marlin 45-70`s do not display the usual and normal pressure indicators, I tend to agree, and at that, possibly this stretch ring indication could be used (In Marlin`s) to tell when to stop. I can tell you that recoil, from 50 gr. up, is severe! Perhaps someone else has seen these stretch rings?
So, here is what I would reccomend,
1. Load until you get a stretch ring, all the while carefully looking for abnormal pressure signs! Back up until the ring disappears, STOP! Use this for max. despite what the manuals say!
2. Get a chronograph, use it as a diagnostic tool along with your good common sense and reason.
3. After getting and setting up your Chrony, generally stay within the bounds that the folks at Speer and Hornady, etc. have published. I found that generally, after all is said and done, that velocities attained closely correlate to their published data. Without the Chrony, you don`t have a clue!!
 

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Individual rifles, and evidently 93%-94% of maunual max. is that rifles individual max. Start low, work up, stop when your rifle tells you to...your load development has indicated where you should stop.

Could be a chamber difference...could be that your componets aren't a perfect match to the ones used in other's loading data (even if of the same brands/headstamps, your lots may be different from their lots)....could be barrel dimentional variation taht increases pressure.
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May be a good time to mention that I've had rifles that invarable would max. out 8-12% below manual max. Every load developed would show unacceptable pressure signss at about the 90% manual level...was getting close to the same velocity as the listed loads, just doing it with 10% less powder.

Others would show the pressure at less than max. and earn much lower velocity than the manuals (plural for a reason) indicate should be earned for that charge. High pressure and lower than expected velocity usaully indiacte a mechanical problem with the rifle that needs to be tracked down (chamber size, throat diameter, bore daiamter, bore smoothness/consistancy).
 

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Such a ring cannot be relied upon to be an indicator of anything more than the case expanding to conform to the chamber upon firing. This ring can show up on fired 405 grain Remington factory loads, which probably run less than 20,000 CUP. The safe operating pressure of the Marlin 1895 is twice that.
 

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IF the sizing dies actaully resize thae case up to that ring, it will re-expand on every firing...evntually will work harden and can expect a seperation. IF the dies don't size that secion or you back off the dies so that they don't, would be better off on subsequent reloadings. May be a candiadate for partial sizing, sizing jut enough to allow free chambering but not so much as to over-work the expaanded section.

Usually pressure readins are of the solid part of the head...just ahead of the rim on the full diameter section of case body...not the 1/5" up from there were the solid head ends and the thin case walls start.

See little gain by pushing ahead anohter 6%...seriously doubt if the game will notice the difference.
 
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