Wednesday, March 30, 2011

Choosing The Right Sabot & Bullet Combo For Your Bore

Looking For This Kind Of 100-Yard Accuracy Out Of Your .50 Caliber In-Line Rifle? It Might Only Take A Different Sabot & Bullet Combo!

By Toby Bridges

Back in the early 1990s, I attended a meeting to help try establish some standards for muzzleloading, including standardizing bore sizes. Knight Rifles, Thompson/Center Arms, Connecticut Valley Arms, and other major muzzleloading rifle manufacturers or importers were there, and so were four or five muzzleloading bullet makers. And, I am sorry to say...Not much ever came of that meeting, other than the realization that the muzzleloading industry is the most non-standardized segment of the shooting and hunting industry.

Back then, in 1993, rifles sold as ".50 caliber" had bores ranging from as tight as .499" (Gonic) to as loose as .504-.505" (White Rifles). And that much variation had created quite a dilemma for those manufacturing bullets for the so-called .50 caliber muzzle-loaded rifles - or for the .45 & .54 caliber rifles at that time as well. This was especially true with "bore-sized" bullets.

The saving grace of this era of muzzleloader development was the plastic saboted bullet. The resiliency and compressability (new word) of the polymers used to produce sabots made it possible to use the same sabot and bullet combinations in various diameter bores - that is, within a reasonable variation of bore diameters. The fact remained that, at that time, a sabot that fit tight enough to be shot with some degree of accuracy from a .504" White Rifles bore could not even come close to being forced into a .005" smaller diameter .499" Gonic Arms .50 caliber rifle. Likewise, the sabot and bullet combo that loaded properly in the tighter bore would literally fall down the looser bore.

In regard to the variations in the diameter of .50 caliber bores of various modern in-line rifle makers, things have gotten somewhat better. And that's mostly due to those companies that were at the outer edges of what was considered a "nominal bore" diameter not selling enough rifles to remain in business. Still, today's popular .50 caliber fast-twist sabot-shooting bores can vary in diameter as much as .002" to .003" - from the same manufacturer, thanks to wear on the tooling used to produce their barrels.

The .50 caliber rifles produced by Knight Rifles all feature Green Mountain barrels, and are some of the closest tolerance muzzleloader barrels produced today. Typically, a .50 caliber Knight in-line ignition rifle will have a bore diameter of .500" to .501". And on rare occasion, a rifle may leave the factory with a bore closer to .502". Thompson/Center Arms .50 caliber barrels are typically .501-.502", with some .50 caliber bores pushing .503". Traditions, CVA and MDM .50 caliber bores generally run .502-.503". And depending on the hardness of the steels used, by about a thousand rounds most of these barrels will show a minute amount of wear - opening, maybe, another .001".

Now, .001"....002"....003" isn't much variation when looking at the gap between the jaws of a set of calipers. In fact, you have to hold it up in front of a bright light to even see an extremely slight gap of .002" between those jaws. But that small amount of difference can make all the difference in the world when trying to obtain optimum accuracy with a saboted bullet - that you are trying to get to group inside of a 2-inch circle at the distance of the length of a football field.

The .50 caliber Knight "Long Range Hunter" I shoot and hunt with more than any other muzzleloader has a bore that's right at .501". This rifle loads relatively easily with the Harvester Muzzleloading .50x.45 black "Crush Rib" Sabot and a .451-.452" bullet. Shooting my favored 260- or 300-grain "Scorpion PT Gold", propelled by a 110- or 120-grain charge of either Blackhorn 209 or FFFg Triple Seven, the rifle will consistently keep groups inside of 1 1/2 inches at 100 yards - often tighter when the operator (me) is up to the task that day.

A couple of fall seasons back, I helped another shooter sight in his well used .50 caliber Knight DISC Extreme model. He was impressed by the accuracy of the Green Mountain barrel of my rifle, and wanted to shoot the same load. With the same powder charge, sabot and bullet, and with the same exact scope (Hi-Lux HPML) as on my rifle, the best we could do was to get the poly-tipped 300-grain "Scorpion PT Gold" to group inside of 2 1/4 inches. But, during loading, I noticed that the Harvester Muzzleloading black "Crush Rib" and .451" bullet tended to load noticeably easier. I surmised that the bore was .001-.002" larger - so switched to the red .50x.45 "Crush Rib" Sabot. This particular sabot is several thousandths of an inch larger in diameter, designed for maintaining more compression of the smokeless powder charges shot out of the Savage Model 10MLII muzzleloader. The slightly tighter fit, which still loads easily due to the "Crush Rib" design of this sabot, made all the difference in the world. Shooting 110-grains of Blackhorn 209 and the 300-grain "Scorpion PT Gold" (with the red .50x.45 sabot), we had his rifle punching 1 1/4 to 1 1/2 inch groups in short order.

Another .50 caliber rifle I shoot often is a prototype of the new Knight "Mountaineer" models. The bore on this rifle I have runs between .501" and .502". And the rifle shoots well with the black .50x.45 "Crush Rib" Sabot and .451" diameter "Scorpion" or "Scorpion PT Gold". Typically, groups with the latter in 300 grains will be inside of 1 1/2 inches at a hundred yards (ahead of 120-grains of Blackhorn 209). After seeing the big improvement with accuracy in the aforementioned .50 Knight DISC Extreme when switching to the slightly tighter fitting red .50x.45 sabot, I gave them a try in the pre-production "Moutnaineer" - and discovered a rifle fully capable of punching sub 1-inch groups.

If you are just so-so pleased with the accuracy you are now getting with your .50 caliber in-line rifle, especially if the groups you are shooting are running 2 to 3 inches at a hundred yards, maybe it's time to do some experimenting. A good start may be to run down to a local machine shop and see if you can get them to measure the land-to-land measurement of your bore. Knowing the exact bore size will help you choose the right sabot. If the bore runs .500-.502", the black .50x.45 sabot may be the one you need to be loading with. If the bore runs .502-.504", chances are the red .50x.45 "Crush Rib" sabot will help tighten those hundred yard groups.

Experimenting to find the optimum sabot and bullet combination for any particular rifle is half the fun of owning...shooting...and hunting with a modern in-line rifle.

One combination I am looking forward to doing more with in the future is with .458" diameter bullets, such as the 300-grain all-copper Barnes SOCOM, the 300-grain all-brass Lehigh bullet, and the 325-grain Hornady FTX. I've been loading and shooting these bullets in my Knight "Long Range Hunter", shooting 120-grains of Blackhorn 209, and have found they make hard-hitting elk combinations that shoots well under an inch at a hundred yards with regularity. While the black .50x.45 "Crush Rib" Sabot has been designed to be loaded with a .451-.452" diameter bullet, it still loads well with the .006-.007" larger diameter .458" bullet. In fact, these bullets with that sabot load easier than the "standard" sabot and .451-.452" bullet combinations I shot and hunted with for years.

(Note: When shooting the 300-grain Barnes SOCOM, I rely on the yellow .50x.45 "Crush Rib" sabot to accomodate the the slight boat-tailed base of this bullet.)


Friday, March 18, 2011

Low Recoil Muzzleloader Whitetail Loads

By Toby Bridges

In recent years, I have taken a number of nice whitetail bucks at ranges of 180 to 200 yards, hitting them with 1,500 to 1,700 foot-pounds of energy at those distances. And more often than not, I've actually watched the animals go down - pretty much where they were standing. However, to achieve this kind of performance there is generally a trade off. To get a modern saboted bullet out of the muzzle at 2,000+ f.p.s. requires shooting a hefty load, say 110- to 120-grains of a hot loose grain black powder substitute, or a 150-grain "pellet" charge. And the recoil generated can be a bit more than many care to tolerate. This is especially true if the hunter happens to be 12 to 14 years old, a small framed female, or perhaps even an elderly person with some physical impairment.

Back during the mid 1990s, while working on a new muzzleloader book, I spent a great deal of time on the range, testing new rifle models and loading components. A local 12-year-old boy had a lot of interest in muzzleloaders and spent a great deal of time on the range with me. He especially enjoyed shooting the modern .50 caliber bolt-action models, which were the new trend at that time. I started him out loading and shooting with a single "50-grain" Pyrodex Pellet and a saboted 250-grain Hornady bullet. At 50 yards, that young shooter could keep them inside of 2 inches with the scoped muzzleloader.

After a few range sessions, I switched him over to 70 grains of fine-grained Pyrodex "P", and had him start shooting at 100 yards. In no time at all, the youngster was punching 3 inch groups at a hundred yards. And on the second day of the Iowa youth deer hunt in September, a fat six-pointer offered him a perfect 70 yard shot - and one very well placed 250-grain Hornady XTP hollow-point put his first deer on the ground.

So, what kind of ballistics does this load produce?

At the muzzle, the light charge of Pyrodex "P" was getting the saboted hollow-point on its way at just over 1,470 f.p.s. That translates into right at 1,200 f.p.e. at the muzzle. This .452" diameter bullet has a b.c. of .147. And at the distance the buck was shot, the load retained just over 850 foot-pounds of energy. The accepted minimum energy needed to cleanly bring down deer-sized game is 800 f.p.e.. The load the boy used to take his first deer had a maximum effective range of about 80 to 85 yards - and I had purposely selected a stand location from which longer shots were not likely. Even out of the lightweight 7-pound rifle, this load generated very tolerable recoil for the 12-year-old.

One mistake many experienced muzzleloader hunters make when getting a younger or smaller framed person into muzzleloader hunting is to start them out with the exact same loads that perform well for them - and that could mean loading heavy powder charges and heavy weight projectiles. The resulting recoil can make it a very unpleasant shooting and hunting experience. One thing is for certain, if the shooter is afraid to pull the trigger, because of that recoil, it is unlikely that they will consistently pull off optimum shot placement.

Most whitetails are taken inside of 100 yards. When starting a hunter with a muzzleloader for the first time, it's wise to limit range to 75 or 100 yards, then develop a load that is comfortable for them to shoot, and which can generate at least 800 f.p.e. at the maximum range that can be shot from the stand they will be hunting. And with today's superior powders and hunting projectiles, it's now a lot easier to accomplish than it was 10 to 15 years ago.

My better half (some say my better 3/4) has shot and hunted most of her life. She tips the scales at just 115 pounds, and is very recoil sensitive. For the 2009 Montana deer season, she decided that she wanted to try hunting with a muzzleloader - for the first time. All of her center-fire shooting had been with mild recoiling rifles in .243 Winchester or .30/30 Winchester caliber, the latter a break-open single shot. And it was one of the No. 209 primer ignition .50 caliber break-open MDM "QuicShooter Magnum" models that appealed to her the most.

Her load was a light charge of Blackhorn 209 behind a 240-grain Harvester Muzzleloading bullet that I had the company's Alan Hensley put together for me. Well, actually all I had him do was install the polymer spire-point tip of the Scorpion PT Gold line up into the funnel-point cavity of the 240-grain Scorpion - to produce a lighter 240-grain Scorpion PT Gold. And the bullet shot so great, the company has now added it to the line.

My gal Christy started with a 70-grain charge of Blackhorn 209 behind this saboted sleek 240-grainer. The light charge of this very energetic powder gets the bullet out of her .50 MDM rifle (26" barrel) at 1,682 f.p.s., with 1,504 f.p.e. This bullet has a b.c. of around .200, and at 100 yards, the load is still good for close to 1,350 f.p.s., and hits with close to 1,000 f.p.e.

Most importantly, this rifle and load does it with very light recoil, and great accuracy. I found that I could consistently keep 100 yard groups right at an inch, and Christy generally kept her groups inside of 2 inches.

She's not much of a horn hunter, and when a big doe stepped out at about 90 yards, one shot put some great eating on the ground - almost instantly. My calculations have this load still capable of delivering 800 f.p.e. to the target out to about 130 yards.

My .50 Knight DISC Extreme, which has been fitted with a conversion to eliminate having to use the red Full Plastic Jacket primer carriers, has always shot well with the 260- and 300-grain Scorpion PT Gold bullets - even when I've pushed powder charges all the way up to 120-grains of Blackhorn 209. Curiosity got the better of me, and I just had to see what the light 240-grain Scorpion PT Gold will do out of the 27-inch barrel of my "Long Range Hunter" version of this rifle.

Now, when heading for the range or the deer woods with this rifle, my goal has pretty much always been to shoot the hottest load that can produce acceptable accuracy - and for me that is to keep them inside of 1 1/2 inches at a hundred yards. This rifle, stoked with a full 120-grain charge of Blackhorn 209 (or FFFg Triple Seven) will get the light 240-grain bullet on its way at 2,188 f.p.s. - with about 2,550 f.p.e. at the muzzle. At 100 yards the projectile is still moving at around 1,800 f.p.s., and plows home with around 1,725 f.p.e. In fact, all the way out to 200 yards, this sleek and light muzzleloader hunting projectile, pushed out of the .50 DISC Extreme by 120-grains of Blackhorn 209, retains right at 1,475 f.p.s., and will take out any whitetail with more than 1,150 foot-pounds of retained energy.

What about accuracy? Three test groups shot with the hot charge of Blackhorn 209 averaged right at 3/4-inch from center-to-center. The best measured .510" . So, what will it do out of this rifle with a lighter, low recoiling powder charge?

With an 80-grain charge of Blackhorn 209 the 240-grain Scorpion PT Gold will get out of the Knight "Long Range Hunter" 27-inch Green Mountain barrel at around 1,740 f.p.s., with around 1,610 f.p.e. By the time this load gets the bullet to 100 yards, it has slowed to right at 1,425 f.p.s. - and hits with 1,080 foot-pounds of remaining knockdown power. This load drops below 800 f.p.e. at between 160 and 170 yards.

Complete with scope and mounts, this rifle weighs in at about 8 3/4 pounds. Recoil with the rifle and load is nil, and accuracy has been exceptional. Most hundred yard groups stay inside of 1 1/2 inches - while some were under an inch.

I have to confess...I'm often inflicted by a case of "magnumitis". It seems that I and many other very performance minded muzzleloading hunters too often forget that not everyone is seeking an honest 200-yard-plus big game rifle. With 70 to 100 grain charges of modern powders like Blackhorn 209 or Triple Seven, the new 240-grain Scorpion PT Gold can deliver the punch needed to bring down deer to 100 yards and a little farther - without the rearward punch that can make muzzleloading a painful and unpleasant experience for smaller framed shooters.

Watch for more on this bullet on the North American Muzzleloader Hunting website at .