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In his article Reloading Primer, http://www.surplusrifle.com/reloading/index.asp, Jamie cautioned every reloader to and use only CURRENT loading data, checked from 3 reputable sources, when selecting powders and charge weights for a pre-selected bullet while handloading.   That statement is extremely good advice, and got me to thinking about loading data, load selection, and medium bore, bolt action Mil-Surp rifles. (Note1.)

I decided to do a quick check of 3 current manuals for the number of powders & loads listed for the most common bullet weights used in one popular Mil-Surp cartridge.  I was going to check the 30/06.  However, since I wanted to make it a quick check, I choose the 8mm Mauser (8X57) instead.  There are page, after page, after page of 30/06 loads!

● Loading Manual # 1:  for 150 & 170 grain bullets, I counted12 powders and 48 loads.

● Loading Manual # 2:  for 150 & 170 grain bullets, I counted10 powders and 71 loads.

● Loading Manual # 3:  for 150 & 170 grain bullets, I counted 32 powders and 106 loads.

That’s a lot of powder and load choices.  Let’s see if we can’t whittle the powder selection down a bit, this will save you some head scratching while trying to make a selection.  Besides if you tried to have every powder suitable for rifle loading, you will have to build a separate powder magazine behind the house (Note.2)!

First, we have to decide what class of load we are trying to achieve before we can make a powder selection.  Lets look the 3 most common classes of loads used in Mil-Surp arms.

► Service Loads   

► Light Loads   

► Cast Bullet Loads   

Service loads are those loads using a jacketed bullet of the same general weight used in military ammunition, and achieving the same general velocities.  These are the most common class of loads.  Again, looking at the loading manuals, there is a clear pattern in powder choices.  That pattern being, IMR 4064 and IMR 4895, these powders are produced by the IMR Powder Company, http://www.imrpowder.com .  Again & again these two powders show up.  No matter which medium bore, bolt action Mil-Surp cartridge I look at, both these powders are repeated.  Going from manual to manual displays the same trend.  Simply stated, these powders work.  The name IMR means Improved Military Rifle.  Let’s take a quick look at the history of the IMR series.

In the mid 1930’s, DuPont's continuing research & development program improved their entire rifle powder line; and introduced straight nitrocellulose progressive-burning types of powder (single based).  A chemical treatment flash inhibitor was incorporated.   This caused less flash at the muzzle and less blast.  All the powders in this line are of the perforated stick variety.  They are cool burning, and the engineered deterrent coatings cause less erosion on ordnance steel.   The chemical composition allows for quick ignition, more complete burning, and more flexibility in charge selection.    

IMR 4064 and IMR 4895 are two of the most flexible powders ever produced.  These two powders (in non-canister grades)  (Note 3.) have been used literally by the hundreds of thousands of tons for both US Military and commercial sporting ammunition.    IMR 4064 is a tad slower then IMR 4895 and develops a bit less pressure.  However, depending on the caliber, and bullet weight used, the slightly faster burning IMR 4895 may be a bit more efficient.  A look at the loading manuals will show which powder is the best bet.  The man looking to load service-type ammunition with jacketed bullets in medium bore; bolt action Mil-Surp rifles need look no further then IMR 4064 or IMR 4895. 

IMR 4064, (new container for 2005) a top performer for service-type loads in medium bore, bolt action Mil-Surp rifles

IMR 4064, (old container)

IMR 4895, another top performer for service-type loads in medium bore, bolt action Mil-Surp rifles.

Light loads are those loads using jacketed bullets, but at substantially less velocity & pressure then service ammunition.  Light loads easy on the guns, the powder keg & the shooters shoulder.  But, that’s not all.  The front sight on most Mil-Surp arms needs to be built up to achieve 100 yard zero with service-type loads.  When using light loads, no such build up is required.  The trajectory of light loads is well within the adjustability range of Mil-Surp sights.   Teaching a new shooter gets easier, if the introduction to the   medium bore; bolt action Mil-Surp rifle is with a light load.  Light loads are much quieter and do not develop anywhere near the recoil of service loads.  The best powder for light, jacketed loads in the in medium bore; bolt action Mil-Surp rifle is SR 4759 (Also a product of the IMR Powder Company) SR stands for Sporting Rifle.   I’ll not get into a big discussion of SR 4759, Jamie’s already done a fine job of covering SR 4759 and jacketed bullets in medium bore; bolt action Mil-Surp rifles, see

http://www.surplusrifle.com/shooting2005/norkragcarbine/index.asp.

SR 4759, a top performer for light loads with jacketed bullet loads in medium bore, bolt action Mil-Surp rifles

Cast bullet loads are those loads using a lead alloy bullet.  The bullet can be cast either by the shooter at home, or they can be purchased already cast by a commercial casting company.  Cast bullets are usually loaded to lower velocities then service type loads.  Cast bullets have 2 very distinct advantages over jacketed bullet loads.  First, they can be just dirt-cheap!  Once you acquire casting equipment, and a source of lead alloy (wheel weights from tire stores are the odds on favorites).  Your cost to shoot drops dramatically!  The second advantage is cast bullets just can’t wear a bore!  Jacketed bullets have a brinnell hardness of 100.  The hardest cast bullet, and most run much less, is about 35.                                                                                                                        

Myself, and fellow Surplusrifle.com Field Editor Ted developed a special cast bullet load that can be used in virtually any medium bore, bolt action, Mil-Surp arm.  The Surplusrifle.com Cast Bullet Load is accurate, light recoiling, low noise, extremely clean burning, and has proven accurate in medium bore; bolt action rifles, both Mil-Surp & civilian.  What powder did we determine as the best powder for cast lead loads in the medium bore; bolt action rifles?  Once again it’s an IMR powder, that powder being IMR 4198.  It’s faster burning then either IMR 4064 or IMR 4895.  Since a relatively small charge (21 to22 grains) of IMR 4198 powder is used, we use filler to hold the IMR 4198 against the flash hole in the case and gain 100% volumetric efficiency.  Precision Spherical Buffer, (PSB) is that product. Precision Reloading Inc sells it. http://www.precisionreloading.com/ For the full story on this load and the loading procedure, see this article.  http://www.surplusrifle.com/shooting/castfiller/index.asp   

A primed & flared brass case, IMR 4198, PSB filler, & a gas checked/sized/lubed lead alloy bullet

It doesn’t take much powder or filler to achieve cast bullet success in medium bore, bolt action Mil-Surp rifles

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