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Frequently Asked Questions! Compiled here is a list of those most frequently asked questions, the answers found here will answer most technical questions with authoritative completeness. Recommendations of bullets for specific applications, bullet harness, bullet obturation, and many other pertinent answers in a concise format.
>> What Bullets For Ruger M77/44, 96/44 And Deerfield Carbines? :: By on 2002-04-02 The WFN profile offered in our lineup is extensive, and provides a bullet for nearly any application in these Ruger carbines. In addition, the cast bullet diameter best suited to these Ruger long guns is 0.432". This is due to the SAAMI specifications for chambering dimensions. As is true with Ruger .44 Magnum handguns, these long guns are also chambered with chamering reamers having throat dimensions of .432"-.4325" in all instances. Although the groove dimensions of these carbines usually measures a very uniform and consistent .429", the large diameter throats necessitate .432" diameter cast bullets for proper alignment going into the bore for best accuracy.
>> Since Beartooth Bullets Are Heat-Treated, Do They Age-Soften? :: By on 2001-01-29 We have very carefully and intentionally chosen our alloy with a target BHN of 21 in mind. When heat-treated to BHN 22, the alloy only loses one BHN point when stored at normal room temperatures. This means that the load you work up today with our bullets will perform the same several years from now when stored under normal circumstances. Our bullets will not ever get softer than BHN 21, from aging or storage.
>> BHN, What Does It Stand For, And What Does It Mean To Shooters/Handloaders? :: By on 2001-01-29 Brinnell Harness Number, or BHN as it is abbreviated, is a relative hardness scale. The numbers are derived from the load bearing ability of of a sample in terms of Kilograms (Kg) supported by one square millimeter (mm˛). This scale is mathematically progressive, in that tripling the BHN number, triples the sample hardness. Conversely, if you cut the BHN number in half, the hardness of the sample is half that of the original. OK, what does that mean to the shooter and handloader? It is the most common measurement of hardness that is applied to projectiles. Here are some common examples:
Now, since the relative BHN of an alloy can be definitively determined, it also stands to reason that the amount of force necessary to deform, or obturate the sample in question also may be calculated very precisely as well. For the purposes of handloading and shooting, this amount of force is most useful when calculated as pounds per square inch (psi.) necessary to deform, or obturate the base of our bullet. To calculate the necessary psi. to obturate the base of a bullet, simply multiply the BHN of the bullet, by 1,422. This simple calculation results in the necessary pressure in psi. to obturate a given bullet. Let's apply this to a bullet of BHN 18. (18 x 1,422) = 25,596 psi required to obturate the bullet! Now, applying this method to the bullet alloys in the chart, we can derive the chamber pressures necessary to obturate the bases of bullets cast out of each one.
We have provided this information for those who desire bullets that obturate at their base for purposes of enhanced accuracy, when not fitting bullet diameters to those of actual cylinder throat dimensions. Many bullet manufacturers do not provide the custom sizing options that Beartooth Bullets makes available to every customer. As a result, you might have to settle for a "generic bullet size" that does not match your revolver cylinder throat dimensions. In that case, these calculations are essential to determining proper load pressures for your particular bullet hardness in order to tweak the load for best accuracy.
>> What About The Idea Of Bullet Base Obturation Being Necessary To Revolver Accuracy? :: By on 2001-01-29 This concept does work to a degree, and can greatly enhance the accuracy of some load/bullet/revolver combinations. However, it is flawed in its conception of being the perfect scenario. Please consider that if the bullet is undersize for the cylinder throat, that it will most likely be laying at the bottom of the chamber (Yes, at the bottom of the chamber! Remember that the chamber has to be bigger than the cartridge for it to easily chamber, and that the cartridge will lay at the "bottom" of the chamber, even if it is just a few thousandths of an inch!) upon ignition of the cartridge. Consequently, when that bullet, that is undersize for the throat of the chamber, obturates under pressure of the expanding powder gasses, it is already out of alignment with the forcing cone and the central axis of the bore by a few thousandths of an inch. Now, considering this aspect, the bullet will already be against the bottom part of the throat of the chamber once the bullet's base obturates (deforms), the odds of that bullet uniformly expanding at its base are really unthinkable. It will expand into the unfilled space of the throat, and thus the bullet will remain slightly off center in relationship to the central axis of the bore, and will remain that way throughout its passage through the barrel! Yes, this bullet will most certainly shoot better than if it did not obturate, in that the powder gasses were sealed in the chamber mouth and the base of the bullet did not become eroded from escaping gasses. This concept does have its limited merits. Now, consider a more precise, and predictable alternative. If the exact dimension of those chamber throats in the cylinder are known, from slugging and measuring, then a bullet of the exact same dimensions can be procured to fire in that particular firearm. This being the case, the bullet will be a firm, snug slip-fit through the throat of each chamber in the cylinder. With a bullet that already tightly fits the chamber throats, it is not necessary for the bullet to obturate in order to seal the mouth of the chamber when that bullet hits the forcing cone and pressures climb. It fit the throat BEFORE firing! Carrying this one step further, the loaded cartridge, with a bullet that is a snug slip-fit in the chamber throats, will automatically center itself in the chamber, due to the tight dimensional relationship between the bullet and the chamber throat. No longer does that loaded round lie in the "bottom" of the chamber, but rather is centered by the bullet in the chamber throat, establishing near perfect alignment with the central axis of the bore, (assuming good cylinder timing and bore alignment), before the projectile is even launched. The result is much more predictable ballistic performance and more forgiving load development, as well as reduced leading in the forcing cone and rearward portion of the barrel. This is the main reason that Beartooth Bullets stresses custom sizing for our customers, and encourages each of our clients to determine the exact dimensions of their firearm chambers to ensure proper bullet size application. When this dimensional relationship described above is properly balanced, bullet obturation no longer plays a role in bullet accuracy or load development. The bullet will already fit the gun, and not need "pressure fitting" by obturation (read deformation).
>> What About Hard Bullets Shattering Or Breaking Up On Large Bone During Penetration? :: By on 2001-01-29 One of the more common of these alloys is linotype with an antimony (Sb) content of usually 12%. Bullets made from this alloy are very brittle, and will predictably shatter when fired at modest velocities if they encounter large bone mass or steel targets. There are also those commercially cast bullets which use a 6% or higher antimony content and are heat-treated to bring their hardness up into the BHN 21-24 range. Although not nearly as violent, nor dramatic, these bullets too can, and do break apart on both steel targets as well as large bone mass in game animals, even at handgun velocities. This brings us to the reason that we use a 3% Antimony alloy at Beartooth Bullets. Although we too heat-treat our bullets to a BHN 21-22 hardness, this low antimony alloy retains the ductile toughness of the un-heat-treated alloy. This alloy, is hard, and tough, not brittle and prone to breaking or shattering like the alloys containing twice to four times the antimony content of our alloy. Our bullets have proven themselves on moose, grizzly bear, Asiatic water buffalo, African cape buffalo, elk, nilgai, zebra, wild boar, moose, eland and multitudes of other heavy boned game animals the world over... usually with complete penetration, and what few bullets have been recovered, most are near perfectly in tact, retaining 90-100% of their original weight when fired at handgun velocities and retaining 70-100% original weight when fired at rifle velocities.
>> Do Beartooth Bullets come lubed and with gas checks? :: By on 2001-01-29
>> What bullet diameter should I order for my revolver? :: By on 2001-01-29
>> How do I measure cylinder throat dimensions for my revolver? :: By on 2001-01-29 Buy Oval Egg Sinkers Here The best method I have found is to use oval egg sinkers (from fishing tackle department), otherwise known as slip-sinkers. These sinkers are perfect for slugging not only cylinder throats but barrel groove dimensions as well. The reasons for using them is four-fold 1. They are usually pure lead, and thus very soft, making them easy to shove through cylinder throats and bores. 2. Their egg shape leaves only a small percentage of their overall dimension which actually bears against the constrictions they are shoved through, unlike a solid lead bullet with lots of bearing surface. This also facilitates ease of shoving them through cylinder throats and rifled bores. 3. They are easy to start into the cylinder or bore since they are egg shaped they are simple to get started. 4. Lastly, and most importantly, they have a longitudinal hole running through them which allows a place for the lead to displace when put through a constriction, thus eliminating "spring-back" or residual memory of the sinker, thereby producing a slug of nearly perfect dimensional characteristics when finished. Use these sinkers, especially in barrels with a VERY light lubricant. Although I recommend seldom for very many things, WD-40 is a great asset here. If starting down the bore of a barrel, I invert a fired cartridge case over the oval end of the sinker sticking out of the bore, give it a sharp rap with a hammer, and the slug is seated neatly into the muzzle of the firearm. The brass cartridge case will not mar the muzzle's crown, nor the bluing, and gets the job done with minimal deformation of the oval egg sinker.
>> How do Beartooth Bullets perform in Marlin Micro-Groove Barrels? :: By on 2001-01-29 1. The barrel generally must be fire-lapped to ease the machine and drill marks from the top of the lands and the chatter marks from the bottom of the lands. This is not to say we remove or eradicate them, just ease, or smooth them out. As a side benefit, wherever there are cut dovetails in the barrel, there are constrictions, and even a slight amount of fire-lapping does wonders to relieve these, and uniform the dimensions of the barrel. 2. Bullet fit is probably the biggest culprit when cast bullet accuracy is elusive in Micro-Groove barrels. The bullets MUST be at least .0005" over maximum groove diameter! When slugging the barrels of these guns (as well as the Rossi Lever action M92's), most people get a real surprise. Click here for the average dimensions we have encountered over the years in various Marlin barrels, not only our own, but those of hundreds of our customers, followed by our recommended bullet diameters for each application. Keep in mind that throat dimensions play an integral part in the bullet-fit equation. (This whole subject is covered at length in our Beartooth Bullets Technical Guide in the Bullet Fit chapter). Click Here for a chart of the average dimensions we have encountered.
>> Which Beartooth Bullets will work in my traditional lever actions? :: By on 2001-01-29 Click Here for a list of Traditional Rifle makes/types and the bullet nose profiles.
>> Heavy bullets jump crimp in my .454 Casull, what can I do? :: By on 2001-01-29
>> Firelapping... What is it and what will it do for my gun? :: By on 2001-01-29 Fire lapping very basically involves shooting a soft, BHN 11, oversize bullet impregnated with a high grade lapping compound through the bore of your firearm at airgun velocities. These abrasive bullets act like self conforming lapping plugs which incrementally remove constrictions in the barrel, uniform it dimensionally and smooth out the tooling and chatter marks in the rifling. Complete fire lapping step by step instructions may be found in the fire lapping chapter in the Beartooth Bullets Technical Guide. In virtually all firearms it will either greatly reduce or totally eliminate both barrel leading and jacket fouling by smoothing out the tooling marks left in the barrel by the equipment used in barrel manufacture and by easing the sharp corners and edges inside the bore which collect fouling. In most guns, there will be at least a modest increase in accuracy potential, to often times dramatic improvement in accuracy from increasing the uniformity of the bore dimensionally, and eliminating the constrictions which are common under dovetails in barrels, and barrel bands. Especially in revolvers where the threaded barrel shank is screwed into the frame of the revolver, dramatic improvements in performance may be achieved. This is particularly true where cast bullets are used in the revolver, because the constriction under the threaded barrel shank (which can be from .002"-. 004" depending on make and caliber), acts like an undersize, bullet sizing die, thus sizing the bullet down under barrel groove dimension, creating an improper bullet to barrel fit. Not only does this condition deteriorate accuracy; it also promotes barrel leading. Fire lapping, properly done eliminates this conditionan. Finally, fire lapping often times increases the nominal velocity achieved with a given load. This is accomplished by a reduction in the friction coefficient of the barrel. Lapping out even a small portion of the tooling marks in a barrel will reduce the friction coefficient of the barrel, at least to some extent. A Note Of Caution You will notice that the first paragraph about fire lapping specified the use of soft BHN 11 oversize bullets. There is a reason for this. The soft bullet will conform and swage down to the tightest part of the barrel, and not "spring back" to near original diameter due to its softness. Thereby the most aggressive cutting action in the barrel is at the point of constriction, and the remainder of the barrel basically gets no lapping action once that soft lapping bullet goes through the constriction. A harder bullet will "spring back" to some degree, and basically lap all parts of the bore at the same rate, thus enlarging everything uniformly, and not addressing the tight spots specifically. I also mentioned oversize bullets. This is to insure equal lapping action not only on the tops of the lands, but in the bottoms of the grooves at the point of maximum barrel diameter as well. If the bullet is less than maximum groove diameter, it will only wipe off the tops of your lands, thus reducing the actual depth of your rifling. There is a popular practice out there in the shooting industry today to use jacketed bullets for lapping. Please use caution, and consider what I just presented, and the following concepts. Most barrels today are .0005-.0015" over what nominal accepted norms are for bore dimensions. Consequently, when lapping with jacketed bullets the only part of the barrel that gets lapping action is the tops of the lands and the bottoms of the grooves never get touched, which is where most fouling and leading occur, not to mention reducing the depth of your rifling by only wiping out the tops of the lands. Fire lapping isn't complicated, but it is tedious, and must be approached systematically with common sense.
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