Saturday, February 23, 2013
Harvester Muzzleloading's "Crush Rib Sabot" Opens The Door To Loading & Shooting A Great Variety Of Bullets
The three bullets shown above easily cover 90-percent of my "hunting bullet" needs. They are, left to right, the 260-grain .451" diameter Scorpion PT Gold...the 300-grain .451" diameter Scorpion PT Gold...and the 400-grain .451" diameter Hard Cast. All come from Harvester Muzzleloading matched with the company's black .50x.45 Crush Rib Sabot. Out of most one turn in 28 inches rifling twist .50 caliber in-line rifle barrels, matched with an optimum powder charge, any of these saboted bullets are fully capable of keeping 100-yard groups inside of the 1 1/2 inch spread more and more of today's muzzleloading hunters are now demanding.
(When a .50 caliber bore is .002" to .003" over sized, more often than not accuracy problems can be cured by simply switching to the tighter fitting red .50x.45 Crush Rib Sabot.)
Twenty or more years ago, a majority of those who hunted with an in-line muzzle-loaded rifle tended to be satisfied with 2- to 2 1/2-inch hundred yard groups. Well, not any more! Today's muzzleloading hunters are now more accuracy and ballistics conscious than any muzzleloading shooters and hunters of the past. They demand a lot from the rifles and loads they shoot - and which they rely on for the quick, clean harvest of the game being hunted. When readily available pre-packaged sabot and bullet combinations just don't deliver the degree of accuracy, or the massive knockdown power needed for some game, these shooters are very ready and willing to begin experimenting with sabot and bullet combinations that simply do not come already matched.
A couple of years ago, I felt the need to shoot something just a bit heavier than 300-grains for elk, and experimented with loading Hornady's 325-grain .458" diameter soft polymer-tipped FTX bullet (designed for use in .45-70 lever action cartridge rifles). I found the flexible, nearly microscopic narrow ribs running the length of the black Crush Rib Sabot to allow me to load the .458" diameter bullet with relative ease in most of the .50 caliber in-line rifle models I use for testing. And with 110- and 120-grain charges of Blackhorn 209, accuracy was great. Shooting the loads out of several Traditions VORTEK models and a couple of Knight in-line models, 1- to 1 1/2-inch hundred yard groups were the norm, with a substantial number of groups clustering sub 1-inch.
The one rifle that gave me a bit of trouble was the .50 caliber Thompson/Center Triumph I have. The bore of this rifle has always loaded tight, which seems to be typical of T/C barrels. Using a solid stainless steel loading rod at the range, I was able to wrestle the saboted .458" FTX down the bore, and two of the first five groups shot with the rifle, 110-grain charge of Blackhorn 209, and Crush Rib Sabot were one wallowed out hole on the target. However, the combo just loaded way too tight for loading in the field with the rifle's ramrod. The same .458" bullet and sabot loaded just fine into the VORTEK and Knight bores. (Hornady .458" 325-grain FTX bullet shown at below left with black .50x.45 Crush Rib Sabot.)
Success with Hornady's 325-grain .458" FTX encouraged me to do some shooting with the Barnes 300-grain polymer-tipped all-copper .458" SOCOM spire point (using a new yellow Crush Rib Sabot for boat-tailed .45 bullets). It too shot great, producing a high percentage of sub 1-inch 100 yard groups. Now, I have the desire to play around even more with other promising .458" bullets.
During the early 2000's, I hunted some with a custom built .50 caliber primer ignition in-line rifle, built on a SAKO bolt-action, utilizing a heavy duty steel primer carrier. One of the best shooting bullets at that time proved to be the .458" diameter 300-grain Barnes "Original". This is something of a semi-spitzer lead tipped copper jacketed bullet, which has a .291 b.c. - which is much higher than the .181 b.c. of the "other" saboted bullet I was shooting at that time...the 300-grain Hornady .452" XTP jacketed hollow point. That difference could be readily seen in the trajectories of the two bullets. Pushed out of the 24-inch .502" 1-in-28 inches bore at close to 2,100 f.p.s., the blunt fronted hollow point dropped a full 18 inches from 100 to 200 yards, while the more aerodynamic semi-spitzer 300-grain bullet dropped only about 9 inches.
Thanks to newer powders like Blackhorn 209, top end muzzleloader velocities are now more easily achieved - with a lower peak pressure. This is especially true when shooting heavier 325- to 400-grain bullets.
At lower velocities (i.e. 1,700 to 1,800 f.p.s.), the 1-in-28 inches bores are now being taxed by some of the heavier bullets, that are in turn longer in length. For most 1-in-28 bores, 300-grain bullets that exceed 1.1 inches in length may not begin to shoot with any degree of accuracy until velocity tops 1,900 f.p.s. Simply put, when one of the longer and heavier bullets travels 200 or so more feet in a single second, it means the bullet has spun more r.p.m.'s in the added distance it travelled during that second. While the rifling twist is the key factor in stabilizing longer bullets, velocity does indeed play a role as well.
The big 400-grain Hard Cast .451" lead bullet shown at the top of this post measures .995" in length, and has been remarkably accurate with 110- and 120-grain charges of Blackhorn 209. With the heftier charge, I can get the big bullet on its way out of the 28-inch barreled standard model VORTEK rifle at 1,923 f.p.s. - which translates into 3,280 f.p.e. Move over Knight .52! Here is one serious elk load. At 100 yards, groups with the bullet stay very close to 1-inch. (Typical group shown at right) Now, if this bullet has one down side, it would be its ballistic coefficient, which I feel is around .220. At 200 yards, my feeling is the load would print, maybe, around 10 to 11 inches down. (This spring I'll do some 200 yards shooting to establish the drop, and to more closely assess the b.c. of this bullet.)
I enjoyed shooting and hunting with the .941" long 300-grain Barnes .458 "Original" semi-spitzer so much about 10 years ago, I now have a desire to play around with the longer (1.160") 400-grain "Original" of the same design to see if I can tap the downrange retention of velocity and energy with the .389 b.c. that Barnes has given the bullet. If I can get the bullet out of the bore at around the same velocity as the Harvester Muzzleloading 400-grain Hard Cast, it is possible that the bullet will stabilize. And if it does, think of the performance it could deliver out at 250 and 300 yards.
At the muzzle, velocity would be in the same ball park as the 400 grain Hard Cast bullet, generting the same level of energy. Thanks to a .389 b.c., the bullet would still be flying along at around 1,600 f.p.s. at 200 yards, and literally plow home with 2,250 f.p.e. In fact, at 300 yards, the bullet would still be speeding along at close to 1,450 f.p.s. - and retain in the neighborhood of 1,825 foot-pounds of game taking knockdown power. This would be significantly better downrange performance than possible with Knight's .52 caliber rifles and loads - again thanks to the extremely high b.c. of the 400-grain Barnes "Original" semi-spitzer .458" diameter bullet.
The buck shown at left was taken at 177 yards with the 300-grain Barnes .458" "Original".
There are quite a few other bullets just waiting to be matched up with a sabot and shot from one of today's advanced in-line rifles - a lot of them of .458" diameter.
Coming up with one's own combination of sabot and bullet is not all about stretching out the maximum effective range of a rifle and load...sometimes it's just to find a more accurately shooting sabot and bullet combination. How many of you own and still hunt with one of the older in-line rifles with the 1-in-32 twist bores used for a number of years by both Traditions and CVA...or one of the even slower 1-in-38 inches twist T/C bores of the early 1990s? There aren't a lot of sabot-bullet combinations offered for these rifles...but there are a number of combos that should shoot well. The shooter just has to put them together themselves.
One that should shoot extremely well would be the short 250-grain .452" diameter Horandy poly-tipped FTX. Loaded with the black .50x.45 Crush Rib Sabot, this .210 b.c. bullet would be a huge step up from the short 240- and 250-grain jacketed hollow-point bullets that most of those rifle owners were forced to shoot...since the bores did such a poor job of stabilizing longer and heavier bullets.
There's a real satisfaction in matching your own sabot and bullet in order to achieve better accuracy or greater retained knockdown power at extended range. Harvester Muzzleloading's excellent Crush Rib Sabot tends to give far more flexibility with bullets ranging from .451" to .458" in diameter than any other sabot on the market. - Toby Bridges
Harvester Muzzleloading Hunter is an affiliate blog of the NORTH AMERICAN MUZZLELOADER HUNTING website at www.namlhunt.com.