The Evolution of Modern Day Muzzleloading
Yes...when the length of the sabot sleeves protrude too far above the point where a bulllet taper breaks over, to form the tip, that extra plastic or polymer can keep you from obtaining the absolute best accuracy. For more on this accuracy issue ... and to take a look at a very simple way to easily tailor sabot sleeve length to the length of the bullet you shoot, go to the link at the bottom of this post. We would love to hear from those of you who have experienced accuracy issues with sabot sleeves that are too long ... and of any solutions you may have come up with. To share your thoughts...please use the comment section for this post.
Right at forty years ago, I "accidentally" loaded a .50 caliber 1-in-60 twist bore rifle with two patched .495" diameter balls ... shot a buck at around 60 yards with the rifle ... and had absolutely no idea that I had stuffed two of the patched 183-grain balls down the bore ... until I walked out to the downed deer. Both balls had hit within a couple of inches of where I had been holding ... and that buck had definitely gone down on the spot.
Here's a link to a new article/report just published on the "Two-Ball Load" topic...
If you have, either on purpose or accidentally, loaded and shot with a two-ball load, please share your experiences of shooting, and especially hunting, with such a load. Use the comment section provided here, or drop us an e-mail at the following e-mail address. - Toby Bridges
However, as "modern muzzleloading" has continued to mature, with more efficient No. 209 primer iginition systems and hotter new muzzleloader propellants adding 300 to 500 f.p.s. to the velocities of the same volume amounts of older powders like Pyrodex ... the thought keeps coming back to me that perhaps the new element of "added bullet speed" just may have had a positive effect on the accuracy of saboted .44 caliber bullets.
Hornady .430" 265 gr. FTX - Harvester .50x.44 CRS
Back in 2012, I published a couple of reports on taking another look at shooting saboted .44 bullets. Those two reports can be found at these links...
More recently, I've been playing around with the .430" Hornady 265-grain FTX bullet shown at left...and I'm now even more convinced than ever that it's time for .50 caliber shooters to revisit bullets of .429"-.430" diameter.
We did not get into shooting with the .430" diameter FTX bullets soon enough to use them on any hunts this fall, but we have shot them enough to be impressed with the accuracy possible. As I write this, I head out tomorrow morning for 10 to 11 days of deer hunting ... and for those hunts, I'll definitely stick with the bullet that has served me well since 2007 - Harvester Muzzleloading's saboted 300-grain Scorpion PT Gold. These hunts will take me right to the end of this month, so look for a report on our shooting with the Hornday .430" diameter FTX bullets in early December.
If any of you are shooting and hunting with the 265-grain FTX, please drop us an e-mail and share your experiences with the bullet...or share them here as a comment below.
I remember when I first began test shooting with some of the bullets, that was definitely a thought that repeatedly popped up in my mind. I first rationalized that, just perhaps, the good folks at Barnes felt that they could gain a little larger slice of the saboted bullet pie by promoting their "heavy weight" offering as a faster flying bullet - when compared to the velocity possible with a 300-grain bullet propelled by the same amount of powder. But then, that also would mean the bullet would come in a bit short on the ballistic coefficient end. Most saboted 300-grain .451/.452" diameter bullets have a b.c.of around .250. The Barnes all-copper boat-tail 290-grain .451" TMZ bullet has a b.c. of .241, while the flat-based TEZ bullet of the same weight has a b.c. of just .223. (Barnes 290-grain TEZ bullet shown above with and without the polymer tip.)
Actually, Barnes DID try to develop the bullet as a 250- and 300-grain offering, but it was another factor which forced the company to cut the heavy weight by 10-grains. That factor was the length of the bullet. As a 290-grain bullet, the TEZ comes in as a 1.2" long bullet when measured with the polymer tip, without the tip the bullet is right at .995" in length. If Barnes had added 10 more grains of copper, it would have likely added another .095" to .100" length to the bullet, taking a non-tipped bullet to right at 1.1 inches, and a tipped bullet to almost 1.3 inches in length. Being slightly boat-tailed at the base, the TMZ would likely be .010" to .020" longer.
Is that too long for the bores of most in-line rifles to stabilize?
I had suspected that the bullet had become just a bit too long for being properly stabilized by the 1-in-28 rate of rifling twist found in the majority of today's modern in-line rifle barrels. At the 2008 SHOT Show, I made it a point to drop by the Barnes booth and ask Randy Brooks, who owned Barnes Bullets before the company sold out to the Freedom Group, if the length had been the reason for the lighter, and shorter, bullet.
"You figured it out!" was Randy's answer.
I witnessed the inability of the 1-in-28 twist to stabilize an overly long bullet when trying to shoot the 1.210" long 375-grain .475" diameter Knight Red Hot bullet out of several .50 caliber rifles with that rate of rifling twist. (Bullet shown in photo at right.) At best, I could punch 3 to 4 inch groups at a hundred yards, shooting with 110-grains of FFFg Triple Seven behind the bullet out of a .50 caliber T/C Omega and a Knight Long Range Hunter. Both are made with a 1-in-28 twist.
When working to develop their .52 caliber bore, even Knight could not get the bullet to properly stabilize out of the 1-in-28 twist Green Mountain barrels used on Knight rifles since 1987. The big bullet had been developed, along with a sabot, for their new .52 caliber models - which ended up being rifled with a 1-in-26 inches rate of rifling twist when put into production. The company had tested with both 1-in-24 and 1-in-26 twist rifled bores - and I ended up with one barrel and receiver assembly for each rate of twist. My average group with the 1-in-26 twist bore ran right at 1.5 inches center-to-center - while the average group shot with the 1-in-24 twist .52 caliber barrel has run closer to 1.2 inches center-to-center.
Beginning in 2000, I did the vast majority of the test shooting with the Savage Model 10ML and 10ML II .50 caliber "smokeless powder" muzzleloaders. Over a five year period, I put more than 35,000 rounds through 9 different versions of the rifle - and quit shooting the Savage rifle when I discovered that it was built with a dangerous "designed in" flaw. But, that's a different story - and one that may need told again...but not here, not now.
The rifle shown in the above left photo was one of those test rifles, and produced MANY sub 1-inch hundred yard groups with a variety of saboted bullets from the early 2000's - and many of those groups went sub 1/2-inch. Back when the rifle hit the market, quite a few muzzleloading "experts" claimed that 1-in-24 twist rifling was "too fast" for best accuracy with saboted bullets. Well, these rifles proved they didn't know what they were talking about. And the loads shot out of the rifles were getting the bullets out of the 24-inch barrels at 2,300 to 2,400 f.p.s.
The buck shown in this photo made the mistake of easing down a long ridge top on opening morning of the season. My stand was located down a long point, allowing me to overlook a well used valley...but on this morning the deer were using the ridge top - 175 yards above my stand location. When this buck stopped to look over the ridge side, looking for does, I had about a 5-inch wide window for a shot - and right in that window was the buck's shoulder. Using a tree trunk for a rest, I held for the center of that shoulder and eased back on the trigger. The saboted 300-grain Hornady .452" XTP threaded itself right up that window - dropping the near 300-pound live weight buck where it stood.
Back in the mid 2000's, I had a chance to play around with a couple of faster twist .50 caliber barrels, to study the effect of 1-in-22 and 1-in-20 twist rifling on a sabot. Well, it wasn't good. When shooting hefty 110- and 120-grain charges of FFFg Triple Seven, I discovered that the centrifugal or spinning force on the sleeves of the sabot would regularly cause the sleeves to tear away from the cupped base. To prevent that from happening, powder charges had to be reduced to 70 or 80 grains - to reduce the rpm's on the sabot.
Left, production 300 gr. Scorpion Pt Gold show with 350 gr. prototype of the same bullet.
The two bullets shown above right taught me a bit more about the need for a rifling twist slightly faster than 1-in-28. The bullet on the left side of the photo is the Harvester Muzzleloading production run 300-grain Scorpion PT Gold. Including the polymer spire-point tip, the bullet measures right at 1.040" in length. Without the tip, the .451" diameter bullet is right at .890" in length. This bullet has been the most accurate saboted bullet I have ever shot out of a modern 1-in-28 twist .50 caliber in-line rifle - shooting from 100- to 120-grains of either Blackhorn 209 or FFFg Triple Seven.
The bullet shown on the right side of the photo is a prototype .458" diameter 350 grain version of the same bullet. With the polymer tip, this one measures right at 1.115" in length, without the tip the bullet goes right at .970" in length. I first shot this bullet out of my 1-in-28 twist Knight .50 caliber Long Range Hunter - shooting 110- and 120-grain charges of Blackhorn 209. The big poly-tipped bullet was a tack driver. Then I shot the bullet out a couple of other 1-in-28 twist .50 caliber rifles, shooting the same powder charges. While those rifles shot the 300-grain Scorpion PT Gold with excellent accuracy, the best I could get with the slightly longer 350-grain bullet was 3 to 4 inch hundred yard groups. However, when I did some shooting with the very same bullet, with the tip removed, those groups tightened to 1 1/2- to 2-inches.
Same Bullet...With...And Without The Tip.
Like most other performance minded in-line muzzleloading rifle shooters, I once felt that the light 3- to 4-grain plastic or polymer tip at the front of modern saboted bullets played hardly any role in the overall length of a bullet...when it comes to stabilization. However, I now feel that when bullet length begins to tax the ability of the 1-in-28 twist to stabilize it...the tip definitely adds some influence to inhibit that ability.
I had also taken along a custom .50 caliber half-stock I had built, using a custom cut 1-in-24 twist barrel. I had been shooting the then new Buffalo Bullet Company conical bore-sized bullets out of the rifle - but had also played around with the new saboted bullet concept introduced by Muzzleload Magnum Products. The rifle shot the saboted bullets with excellent accuracy.
My goal had been to convince Tony that to market a rifle as modernistic as the MK-85 would take giving muzzleloading something of a new twist ... to properly stabilize MMP's sabots and pistol bullet combinations. My 1-in-48 twist MK-85 simply would not shoot the sabot and bullet combos with any accuracy - while the 1-in-24 twist custom half-stock barrel commonly produced 1 1/2- to 2-inch hundred yard groups. It took only about an hour of shooting to convince Tony that his Knight rifles needed a faster twist bore.
By fall of 1986, Modern Muzzleloading (a.k.a. Knight Rifles) was building the MK-85 with a 1-in-32 twist barrel, and it shot saboted bullets extremely well...but definitely shot best with the shorter 240- and 250-grain bullets. Longer 300-grain bullets, like the Hornady XTP, just were not being adequately stabilized. I hooked Tony up with my good friends at Green Mountain Rifle Barrel Co. - and by fall 1987, the rifles were being built with a snappier 1-in-28 twist.
The buck in the photo at right was taken at 100 yards with one of the first four 1-in-28 twist test rifles. Tony had sent the rifle to me in late summer...and by the time season opened early that November, I had already put more than 500 rounds through the rifle - and it shot the saboted 300-grain Hornady XTP with exceptional accuracy.
Bridges with a nice northern Missouri buck, taken with one of the very first 1-in-28 twist in-line rifles.
Perhaps, but it now seems that the 1-in-28 twist is exactly what's holding back taking modern muzzleloader performance to the next level. It has become very apparent that when bullet length falls somewhere in between 1.1" and 1.2", that rate of twist simply cannot properly or consistently stabilize the bullet.
So, who will be the modern in-line rifle maker to step up to the plate and take the lead with a 1-in-26 or 1-in-24 rifling twist? One or the other of those twist rates is destined to become the next new standard for modern in-line muzzleloaders!
Modern No. 209 primer ignition systems are likely as advanced as they will become, for at least another 20 or so years anyway. With new "non-smokeless" black powder substitutes, getting a bullet out of the muzzle at 2,000 f.p.s. has become very commonplace these days. Now, it seems the secret to advancing modern muzzleloader performance lies with improving the saboted bullets the majority of hunters are using these days. To increase the effectiveness of these bullets requires increasing their ballistic coefficients - which means making them longer, more aerodynamic and likely even heavier. Accuracy with such a bullet will mean giving muzzleloading yet another new twist. - Toby Bridges, NORTH AMERICAN MUZZLELOADER HUNTING
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