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"Max Loads" And Handguns
Marshall Stanton on 2001-03-20

There seems to be a fixation today that has permeated the firearms and handloading circles upon "max loads" in handguns.  Fixed on this obsession I fear many are headed on a crash course with disaster and disappointment!  Every day we see new posts by shooters seeking "max load" for this or that hand cannon.  A road of ruin lies ahead!

Never before has the handloader had such access to excellent handloading resources.  Good, credible loading data abounds, in a multitude of loading manuals, many of which are free from powder manufacturers for the asking.  There are online reloading databases and excellent articles posted on the net.  Combine this with the most advanced, most precise reloading equipment ever offered to the individual consumer, and the very affordable price of chronographs these days and there is no reason to enter into unknown "red zones" of pressure!   

All prudent and safe handloading begins by cross referencing loading data from at least two reliable, credible sources, preferably that published by powder companies.   If using a load shared by a friend, off the internet or from a magazine article, be sure to compare that data with reliable published data elsewhere.  Then, proceed with caution and great expectations.  Once having cross-referenced your data, then pick a safe, below maximum charge to begin your loading development.

This article is pointed primarily at the .454 Casull and load development in this cartridge.   There is a constant drive towards more, more and still more power from this cartridge, especially with the introduction of both the Taurus Raging Bull and the Ruger Super Redhawk chambered for this round.  Yes, all the firearms produced for this cartridge are superbly strong, and yes, they are proof tested to pressures well beyond normal working load levels.   However, they too have upper limits to pressure, and a safety margin that need not ever be exceeded.

A cautionary statement concerning  the tight tolerances of the FA revolvers not producing significant case head expansion is in order here.  A common method of determining max working pressures in handgun cartridges is to measure case head expansion with factory or factory equivalent loads, then develop handloads which don't exceed that level of case head expansion.  This method does not apply to most Freedom Arms Revolvers!  Freedom Arms guns have such tight tolerances that more often than not, your loads will be well into the "red zone" and still not show significant case head expansion.  Primers, especially in the Casull, are a poor indicator, as you are using rifle primers in a handgun case, the primer cups are significantly thicker and tougher than are handgun primers... consequently by the time you get pressure signs via primers in the .454, you are well into dangerous waters as a rule!

If you are seeking to safely maximize the performance of your handgun, the most productive piece of safety equipment you can own is a chronograph!  If you don't own one, wait on other shooting frills, and go spend the bucks and buy a $70 Chrony!  Why?  Because that chronograph will tell volumes about your load status! 

 In using both H110/W296 as well as AA1680 in your .454 Casull,  these powders thrive on pressure, and reach their most efficient burning at the top 5% of the pressure envelope.  You can use this to your advantage in determining optimum loads with your chronograph.  You will notice a few things happening as you are cautiously working up a load using these powders.  First, pay special attention to the ES  (extreme spread) when shooting strings during a load workup.  In loads that are well below the upper end of the pressure envelope, there will be large, and sometimes very large ES readings.  As you begin to approach the best efficiency threshold, those figures will drop, sometimes right into the single digits!

Once into the low double digits for your extreme spread figures, then go slowly, as the sweet spot will only be a few tenths of a grain one way or the other on a good load for peak efficiency.  I rarely have tuned a load with these guns, where when the ES over the chronograph showed single digits, that accuracy wasn't' very good to superb!

Now, another essential tell-tale sign to look for is velocity increase when upping powder charges incrementally.  At the low pressure end, you will see very little change in small powder charge increases with H110/W296 and AA 1680, then as you begin to approach the pressure envelope that produces efficient burning of these powders you will observe significant velocity jumps with negligible powder increases.  As you begin to increase charges, and the velocities are climbing, rather predictably with each upward increment, you will also see the ES figures dropping.  Somewhere in this progression, you reach a point where the load does what I refer to as "flatline", where powder increases give very little to no velocity increase for the extra fuel added to the fire.  At this point stop!   Absolutely stop!  You have reached a point where the load has maxed out the efficient burning threshold of the volume of powder loaded.  Any increase in powder at this point is only spiking pressures!

Something to keep in mind:  Increasing powder charge weight 10% in this application will only net a maximum of 7% velocity increase, but at the same time increase pressures 20%!

After having taken detailed notes during your load development, you should see a pattern developing of velocity to powder in the form of progressive increases.  This trend is most easily evaluated when you plot your powder vs. velocity on an X-Y graph in a good spreadsheet program.  This way you have a graphic representation of the velocity curve in relation to your powder charges.  Now, if you also plot your ES figures for the same loads on that X-Y graph, that point where you have the lowest ES, with velocities that are proportionately increasing with added powder will be your top, safe load that will also have the potential of being your most accurate load in terms of burning efficiency.

From this established point you can tinker with a few tenths of a grain one way or another to fine tune the load on paper.

Now, having said all this, it is very applicable to the .454 Casull since it operates safely at the high pressure thresholds was designed for! Also keep in mind that this method is outlined assuming the use of W296, H110, V-N110, AA #9 or AA 1680 powders, those which give the best overall performance in the .454 Casull. 

This method is much more reliable than many of the other traditional "max load" tests.

Here I will inject some bullet performance and ballistics information.  Consider using the Beartooth .452"-340g LFNGC bullet in the .454 Casull.  Below are listed some velocities in 100 fps increments and resultant permanent wound channel calculations as well as trajectory comparisons at those same velocities as calculated from our resources on Ballistician's Corner http://www.beartoothbullets.com/rescources/index.htm 

Beartooth Bullets .452"-345g WLNGC Bullet With .360" Meplat

Impact Velocity In fps.

Calculated Wound Channel In Inches 

1200 1.08"
1300 1.17"
1400 1.26"
1500 1.35"
1600 1.44"
1700 1.53"

Trajectory Beartooth Bullets .452"-345g WLNGC Bullet  .218 B.C.

Velocity (fps) 50 yds 75 yds 100 yds. 125 yds 150 yds
1200 1.5" 0.0" -3.4" -8.8" -16.4"
1300 1.3" 0.0" -2.9" -7.6" -14.2"
1400 1.1" 0.0" -2.6" -6.7" -12.5"
1500 .9" 0.0" -2.2" -5.8" -10.9"
1600 .8" 0.0" -1.9" -5.1" -9.6"
1700 .7" 0.0" -1.7" -4.5" -8.5"

When looking at the performance of this bullet, notice the very little difference that 100 fps velocity truly makes in both terminal results and in trajectory!   Under field conditions, that extra 80 or 100 feet per second that strains equipment to its very limits, does nothing in a practical sense to enhance actual hunting performance.   All we are doing by pressing onward towards the final FPS is making more muzzle blast, more recoil and stressing our gun and brass to the extreme, only to satisfy our craving for superior numbers, not necessarily superior performance!

Keep in mind the performance level you actually need for the conditions under which you will use the weapon/load combination, be realistic, then develop a load towards that end using the information outlined in this article.   The result will be top performing loads that are superbly accurate, brass that will last because it isn't being punished, and the satisfaction and comfort that you aren't stressing your equipment, yet at the same time you aren't sacrificing performance.  If all these criteria are met, don't worry about it being a "max load"! What you have is a very safe, performance driven load, safely making use of the full potential of your firearm and bullet. 

Be safe and enjoy!
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