A Closer Look at Savage 10ML-II Accuracy Loads
First, the requisite disclaimers. Please Note: Randy Wakeman, his agents, heirs and assigns, hereby disclaims all possible liability for damages including, actual, incidental and consequential, resulting from usage of the information or advice contained in this message. Use the data and advice at your own risk, and with extreme caution.
The following presentation is offered for those who have more than a casual interest in Savage 10ML-II preferred loads. The information here is to be considered theoretical in nature, and any use of it is at your own risk. By reading further, you consent to this.
In discussions with Del Ramsey of MMP, the sultan of sophisticated sabotry, I tried to pin Mr. Ramsey down to a few trends. Not an easy task, as the variations from muzzleloader barrel to muzzleloader barrel, and those from manufacturer to manufacturer, are incalculable. However, there are a few "generalizations" that Del is comfortable with. After endless experimenting with different formulations and variations, we now have relatively soft MMP sabots that can perform like never before. Given the severe restriction of being loadable from the muzzle by ramrod, current formulation MMP sabots are at a level impossible to achieve a decade ago.
As a generalization, like many gasketing applications, the thinner the sabot is the better sabot. This is not to say that .43 / 50 and .40 / 50 sabots do not perform extremely well with moderate loads, or sometimes even higher performance loads, they can. However, the likelihood is that the .45 / 50 and .458 / 50 sabots will get us up to speed quicker, with less temperamental loads over wider ambient conditions and bore conditions.
I've heard a lot about "plastic fouling" over the years. Yet I have never experienced it, regardless of gun. Del Ramsey has not either, nor has Henry Ball. The only thing I can say about it is that if it is a problem, there is a good possibility your load development is going distinctly down the wrong path and you are exceeding one or more of the generalized thresholds mentioned in this article.
To home in on the optimum combination for an individual gun, the best thing anyone can do is call MMP at 1-870-741-5019 and order an array of four packs of different sabots to cover the bases. They are the MMP short black sabots with a concave base for .451 / .452 bullets, the black HPH12 longer petaled, stepped base sabots for .451 / .452 bullets, the HPH24 black sabots (same as the HPH12, but around .002" smaller assembled with bullet OD for easier loading), and the orange .458 / 50 sabots that give us the opportunity to use the variety of .45-70 rifle bullets out there.
All these sabots are made from the same secret MMP formula that Del keeps inside the crocodile-infested moat that he inherited from the late Jack Benny. Rumors that Mr. Ramsey is actually Jack Benny may persist, but I believe they are unfounded. Admittedly, Mr. Ramsey and Mr. Benny have not been seen in the same room at the same time, but until I hear a violin scratching away and a call for, "Rochester!" it has to be written off to a type of Elvis syndrome. I understand Mr. Ramsey has spent some time near Waukegan, Illinois, but that is sheer coincidence. It's time to move it along. Past time, actually, but shooting MMP sabots is a wonderful pass time.
There are other generalizations for all-around, all condition sabot performance. A 35,000 PSI peak pressure limit is a generalization, and a rate of barrel twist no tighter than 1:22 is another. With our Savage endeavors, good load design means protecting our sabot. The 1:24 rate of twist allows the Savage to perform well with the 300 grain bullets for which it was designed. Harder to stabilize pointy ogives and boat-tailed bullets are addressed as well where the 1:28 rate of twist may not be quite enough. I've had very good luck with .45-70 Government bullets; those bullets being generally used in 1:20 twist-rate barrels. The Savage 10ML-II's 1:24 barrel coupled with a notch higher velocity has proven it is one of the very few muzzleloaders today that can effectively use 45-70 bullets, and that is why the orange MMP sabots are so valuable to the 10ML-II shooter.
Another generalization is the velocity limit of today's sabots. The generalization is 2500 fps maximum muzzle velocity. For reliable load work, I believe it is prudent to stay below both generalized ceilings: 35,000 PSI peak pressure and 2500 fps MV.
For starters, let's take a peek at an interior ballistics prediction of a supremely accurate Savage 10ML-II load, the load most used by Savage factory shooters.
Here, peak pressure does not come near our 35,000 PSI sabot protection threshold so there is little danger of accuracy-robbing sabot damage. By the time our bullet travels four inches, back pressure has dropped off to less than 14,000 PSI, making the rest of the ride relatively easy for this combination. Normally, the combination is a .452 Hornady XTP and the short, black MMP .45 / 50 sabot powered by Vihtavouri N110 powder. A Savage preferred load, N110 does very well in conjunction with 250 grain class bullets, but not nearly as well with heavier bullets. This load has passed my five shot repetitive 3/4 MOA at 100 yards criteria.
Next up is the perennial Henry Ball & Co. favorite, 44 grains of Accurate Arms 5744 powder. It offers many advantages for the field. It is easily loaded with Lee yellow plastic 3.4 cc dippers, easy ignition even with loose fitting sabots, and by virtue of its 20% nitro content it is exceedingly temperature insensitive.
Accurate Arms 5744 is equally at home with 250 or 300 grain bullets. It does break our personal load design parameter of 35,000 PSI by a small amount with 300 grain bullets (not with 250 grain bullets), but years of testing have proven it to be an ideal 10ML-II load. Testing reveals slightly lower velocities (and pressure) than our prediction; about 100 fps less at the muzzle (2080 fps).
True to Del Ramsey's generalization, shooters have reported an accuracy loss by going above 44 grains, contingent on gun. This is a Savage Arms preferred load, and has accounted for over 1500 head of deer in one area of Coastal Carolina alone. With Barnes 300 grain MZ-Expanders, this has been a repetitive sub-3/4 MOA 5-shot grouper.
As a footnote, Barnes currently supplies MMP HPH-12 sabots along with these bullets. Coincidentally, on the Barnes site, it is mentioned that in some cases, a 1:28 rate of twist may be insufficient for this bullet. Without question, the Savage 10ML-II 1:24 barrel is sufficient. My last four shots with this bullet, powder, and sabot combination has accounted for four quick kills. There is more to the picture than "just" peak pressure; after eight inches of bullet travel back pressure has dropped to less than 7500 PSI. It is hard to conceive significant sabot base stress at that point and beyond.
Now, for a look at what is currently my favorite load, employing the often-overlooked orange MMP .458 sabot, and the also overlooked high-BC "Barnes Original" spitzer soft-point 300 grain .45-70 bullet:
Best suited for 300 grain bullets, as is the Savage 10ML-II, this tack-driving load comes nowhere near the 35,000 PSI pressure barrier we have set, yet chronographs a remarkable 2300 fps at the muzzle. Not only a better than 3/4 MOA load, it is an amazingly flat shooting low pressure load with manageable recoil. For an upcoming pronghorn hunt this fall, this loading gets the call. Vihtavouri N120 is a fabulous powder for the Savage 10ML-II, and a load like this depicts it well. Not breaching 28,000 PSI peak, and featuring about a 93% powder burn, it is a beauty. I've found it to work wonderfully with Barnes 300 MZ-Expanders as well.
Lastly, here is a loading that exceeds my recoil comfort level, but allows the use of true 350 grain rifle bullets, in this case, the Barnes "X" bullet, for extremely tough game:
It begins to more fully exploit the versatility of the Savage 10ML-II, and uses Accurate Arms 2015 powder, which achieves a "balanced load" with 350 grain bullets. The same MMP .458 orange sabot is employed, and again the accuracy is impressive. Our prediction does not break even 25,000 PSI peak pressure; yet, this load develops over a TON of energy, at 250 yards.
Savage has the tightest barrel standards in the muzzleloading industry, but there are still tolerances of +/- .001". As Del Ramsey has reminded me, two thousandths of one inch is a lot to a sabot. Naturally, most of us don't like to really accept the fact that all rifles are individuals, but that's the way it is and always has been.
By starting with MMP current formulation sabots, at least we have a known quantity with which to work up our loads. If we use a pile of prepackaged bullets with sabots, there is no way to tell from box to box what we are working with. It is frustrating to work up a load with a box of bullets, and suddenly find that "our load" has vanished with the very next box. Fresh product direct from Barnes eliminates that problem, but with most bullet makers what sabot is in the box is an unknown.
It is critical that our assembled sabots fit our bores, lightly engraving and rotating on the way down. If they fall down, they are unlikely to group. If we come close to injuring our naughty bits when forcing them down standing on a range rod, they are not useable in a hunting scenario.
Since we have armed ourselves with the MMP 4 pack of sabots we can, in many cases, turn a pig's ear into a silk purse. To give you a specific example, I'll cite a recent bullet I'm now working with: the Speer Gold Dot .454 Casull (.452) bullet. It won't easily go down my gun's bore with an HPH12; the assembled OD is .505". It is about .505" with the MMP short black sabot as well, but loads easier due to its smaller base and perhaps the shorter petals. It is still a bear to get down the bore. It mics .502" with the HPH24, though, and we are in business--it fits beautifully.
That is the hierarchy of MMP sabots as best I can determine, the easiest to load being the HPH24 (which may be too loose in many cases), then the MMP short black, and the HPH 12 as the snuggest of the group. There are other combinations to try as well, as a bullet with a short bearing surface is automatically a bit easier to load than a longer heavier bullet of the same construction.
For example, we may not like the way a 300 grain Barnes MZ-Expander loads as supplied (HPH12), finding it just a bit too tight. Yet, a 250 MZ-Expander may have the precise loading feel and fit we are looking for. Alternatively, we may want the extra BC and sectional density of the Barnes 300 grain MZ-Expander that we have trouble loading as supplied. Substitution in of an HPH 24 sabot may give us exactly what we seek.
I'm mentioning all this because sabots are easily the most ignored component of accuracy. Few of us know where all of our sabots come from, how old they are, and so forth.
To add to the mess, you likely have heard terms like "high pressure sabot." There is no such thing; MMP has never heralded a sabot like that. Nor is there such a thing as a "low pressure sabot." How often have we all heard the lament, "This sabot loads too tight"? That may be what we experience, but it really isn't the case at all.
Del Ramsey is a very intelligent man, but his sabots are brainless. The dumb old sabot has no idea what bullet is going into it, what the precise dimensions of that bullet might be, much less what the land-to-land dimensions of our gun's bore might be. It is a one time task, but it is our job to find the combination or combinations best suited for our gun. Sabot fit is the most important factor, in my opinion, in finding repeatably accurate loads, and accuracy is our reward.
If you have hung in with me this long, congratulate yourself. You obviously care more about getting the most out of your gun than do most folks.
We've stacked the deck in our favor before we began. We are using traditional, proven Savage 10ML-II loads, or we seek sub-35,000 PSI loads (and sub-2500 fps loads) that take sabot damage out of the equation. We are also using the generally stronger, more accurate .451- .452 black or .458 orange MMP sabots. We are also using current formulation MMP sabots, not playing Russian Roulette with stock of unknown age and formulation. It may read like an arduous task to some, but it isn't, really. It is the difference between just wondering how your gun will shoot today, and knowing that it will shoot supremely well. That is all the difference in the world.
Copyright 2005 by Randy Wakeman. All rights reserved.