Home Forums Hunting & Shooting Ask The Gunwriters Pressure Signs

Ken:
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<br>First, I want to thank you personally and publicly for agreeing to put yourself in the crosshairs here. I'm sure I speak for many when I say, "We are honored, sir."
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<br>My question relates to pressure signs. Most of us know the basics ... flattened primers, sticky bolts, brass flow, shortened case life.
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<br>However, it seems that there is no truly reliable way for a layman without specialized equipment to actually know when he's getting into the hot zone.
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<br>What do you recommend? (I am staying away from the case head expansion method for now).
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<br>Thanks.
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<br>Rick Bin

First, get over the idea of loading "up to the edge." The best interior and down-range performance favors moderate chamber pressures -- as proved repeatedly by the plethora of excellent low- and moderate-pressure cartridges and rifles.
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<br>A difference of 100, 200, even 300 ft/sec in muzzle velocity adds or subtracts very little in either the impact energy or the trajectory down-range, but it makes a great deal of difference in the average peak chamber pressure and the accuracy life of the barrel. (Throat erosion is a function of the peak pressure and its related temperature.)
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<br>So the key is to be satisfied with moderate loads -- loads that don't give you sticky bolts or stubborn resistance to extraction. If you HAVE to have more performance, get or rechamber to a larger cartridge. Loading a .25-06 down to "hot" .257 Roberts performance makes a lot more sense than trying to make a .257 Roberts deliver .25-06 performance.
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<br>SAAMI's maximums are MAXIMUMS, established for SAFETY, not for optimum performance. Factory loads are loaded for sales competition, not for optimum over-all performance. The obsession for loading to outdo the performance of factory ammo is very close to the same as the fruit offered to Eve in the Garden -- "foolish" is the nicest I can say about it.
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<br>My article "Forget Feet. Think Inches," in a back issue of VARMINT HUNTER Magazine, spells out specific details. For here and now, all I can say is "Forget loading to the edge. Load ammo that you don't have to wonder about." This means stopping -- and backing off with your powder charge -- at ANY sign of high pressure. You know -- hard bolt lift, stiff extraction.
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<br>You don't need any special smarts or tools for this kind of loading -- but it's smart loading.

When I have time to look 'em up, I'll post data that show specifically and in detail how an increase or decrease in muzzle velocity goes along with
<br>(a) a greater effect on peak chamber pressures (therefore on safety and barrel life)
<br>and
<br>(b) no practical effect on down-range impact energy or trajectory.

I know it's not a cartridge gun but I found that my .50 cal Hawken copy is much more accurate with a charge of 90 grn's Pyrodex rs than 120 grn's of the same so I started loading down for it. Now it makes sense to me, more ain't always better. Thanks.

T Lee, I found the same thing as you did with my 50 Hawkin, I shoot 95 gr xxx black under a patched 170 gr round ball. my rifle is sighted in a 100 yrds. I generly can shoot 2" groups. When i started shooting this rifle 20+ years ago I did not have a chronograph. So I loaded powder by volume until my bullseye would remain the same place on the target no matter what load I used IE: 95, 100, 105 .... my accuracy was best at 95gr 2" groups at bulls eye, the group grew as increased powder was applied but still remaind at same elevation on target. So I found my rifles "sweet spot" every thing else was just smoke and recoil. i believe the 95 gr load is optimum, every thing else is burning out side of the barrel and perhaps upsetting the ball a bit.
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<br>Bullwnkl.

BW, I am using a 385 gn hard cast hollow base hollow point from Hornaday. At 100 I am getting the same 2" groups consistantly, took an elk 2 years ago at a paced off 68 yrds, two steps and down what a day that was! I must agree, any more powder is wasted out side the barrel as smoke and flash.

I believe that muzzle loaders are even more persnickity in their liking for a load than cartridge rifles. All of them that I have fooled with have one load that they like and you might as well shoot it and be happy because you are not going to do any better with that particular rifle.
<br>I had a Hawken 45 that only liked 90 grains of 2F and a maxi ball.
<br>A Traditions 50 that just loved sabots and 100 gr Pyrodex.
<br>My favorite was a 50 Long Rifle flinter that shot patched ball and 75 gr 3F and barfed up every thing else.
<br>Never did understand the desire to "magnumize" a front loader. Lordy, they fought a whole war mainly on fifty-eight caliber mini balls and 60 grains of powder.
<br>BCR

Ken. First, thank you for giving yourself to this format.
<br> Would you comment on what I am seeing.
<br>I have a load that I have carefully workup up. That is, I started with a know ogive measurement (-.025 from the lands) and the medium powder charge for the listed bullet/powder combo.
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<br>Using ONCE fired brass, I began shooting 3 shot groups, increasing by .5 gr untill I reached the max listed load.
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<br>The rifle shot consistant .75" groups at each powder charge. There were no signs of excessive pressure ( flatened primers, sticky bolts, or lenghtened brass after sizing). I am at the max. average powder charge. One reloading manual gives a max. charge of +2 gr. higher than what I am shooting. I feel confident I am operating in safe pressure levels.
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<br>This is now the FOURTH time I have loaded this brass. I have not had to trim the cases after sizing, but I have noticed that when priming some of the cases the primer slips very EASILY into the primer pocket.
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<br>I just noticed that some of the fired cases of this FOUR times reloaded brass have "flattened primers", and some do not. There are still no other signs of pressure.
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<br>I BELIEVE that those flattened primers are the result of the "loose" primer fit that I noticed when priming the cases and not signs of pressure. And that that loose fit is causing the primer to move back aginst the bolt causing them to flatten, while the others are not.
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<br>What would you advise?
<br>Thanks
<br>Tom Moody

I don't know what Dr. Howell would say to this. But, this is my system.
<br> I start at a standard starting load. The older I get, the more I like the idea that I don't need the last 100 fps.
<br> In the warmest temperatures I will use this rifle, I go up in charges until I get some pressure sign on once fired brass. Previously used brass will give false readings if it's been pushed hard. Sometimes these pressure signs are just a visible ejector mark. At that point, I back off a full 5%. Then, if necessaty, I go a little lower for the best accuracy. Usually I'm a little less than this maximum. As I use the load, I keep records as to primer pocket enlargement, and general case life. If I don't get 8-10 reloads, I cut the load.
<br> The point is that loading manuels are guides. Not the word on a combination. Rifles vary.
<br> I, too, like the idea of one case size larger. My .257 Roberts is a .25-284. My 7X57 is a .280 Rem. If I can get a little more, fine. If not, well, it will work.
<br> I've found that a computerized ballistics program is very helpfull in comparing loads. 100, even 200 fps., makes very little difference. E

Ken and I (and others) butted heads on this over on the old Shooter�s board some time ago. The thread was about reliable ways to measure pressure and danced around a whole bunch of subjects.
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<br>My �irk-shun� was his recommendation to load cartridges in the 50,000 psi range and lose 100 or 150 or even 200 fps in the process. If I wanted lever action pressure then why buy a bolt action? If I wanted .308 performance then why did I buy a .30�06? If I wanted .30-06 performance then why did I buy a .300 Win. Mag. Etcetera, etcetera, and so forth.
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<br>Guess Ken�s head is harder than mine as this wisdom finally sank in. I bought QuickLoad (again on his recommendation) and ran a whole bunch of scenarios through it, testing pressure/velocity/trajectory relationships. You really don�t lose much at all in downrange performance by sacrificing 100 fps, but you gain anywhere from 5,000 to 10,000 psi in that �safety zone� that lies between satisfaction and disaster.
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<br>Now I won�t go into all of the ways I determine that safety zone, but suffice it to say if I can safely get somewhat over 2800 fps from a 180 grain bullet in a .30-06, the animals I shot over in Africa this spring were JUST as impressed when I shot that bullet at 2750 fps. Now if those animals were killed right now with that 180 at 2750, how do you think they will react to a .300 Win Mag, which is capable of 3100 fps with that bullet, throwing it at a sedate 3000 fps? Hmmm, funny, they ain�t saying much.
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<br>Ground squirrels are just as impressed by my .22� barreled .223 throwing 55 grainers at about 3050 to 3100 fps as they are pushing them to 3350 fps. I�m happy, my rifle is happy, the cases sure are happy, only the ground squirrels are unhappy with this arrangement.
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<br>I believe I read where friend Big Stick follows the same principles with his love of AI cartridges. Give the powder more room so you can put more powder in to achieve more velocity without increasing the pressure. Or, use slower powders at lower pressure in the same case.
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<br>Anyway, without further rambling, let me say that this is a very wise course of action to follow. Try it, you�ll like it.
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