The bullet groups which struck the target more closely together left the barrel as it had vibrated to near the end of its movement and was nearly stationary at that moment. The bullet groups which impacted the target making a larger group size left the barrel when it was still moving.
Chose a loading from among the groups which stayed closest together. Load up about 20 rounds and put your strongest powder charge in the first one while making each one thereafter having 0. Record on a clean target, the impact point for each shot. As you get into the stronger powder charges your bullet holes will climb upwards on the target but the rise will NOT be uniform. Some shots will clump together and others will spread apart. Those shots which clumped together even if their powder charges were quite different represent bullets which left the barrel while the barrel was at its extreme vibration point as mentioned in method 2 above.
Pick a load which is in the middle of one of the powder charge ranges that produced a small bullet hole spread and load up at least 5 or 10 using the exact same methods.
Fire these loads making every effort for consistency in how you bench the rifle and hold it. If you can duplicate the small group size originally produced, you have hit upon "one" of the loadings which your rifle likes and which will minimize inaccuracy caused by barrel vibrations.
If you seem satisfied with your test load, now is the time to refine it even more by making ONE CHANGE at a time to primer, powder, compression, bullet alloy, lubricants etc. What you have after use of a long drop tube or the use of a vibration device, is a "settled" powder charge not a compressed charge. All black powders respond for better or worse, when additional compression is applied. By far, the usual result of applying additional compression results in improvement to both accuracy and velocity.
Sometimes you will also find lower barrel fouling as well. Match grade ammunition should always be compressed using a special "powder compression die". Using the bullet seating operation to compress the powder strongly may deform the soft bullet ogive in a manner so slight as to be unseen by your eyes, resulting in inaccuracy and possible jamming in the chamber.
You may find best speed or accuracy is obtained using an uncompressed charge or that compression as high a. Due to grain crushing effect with excessive powder compression, it is not recommended to compress black powder more than. Note that when duplicating original military type ammunition used in Springfield Trapdoor models, very high amounts of compression is required.
This should not be done for non-military type reloading in Trapdoor and other types of BP rifles. If a significant amount of air space is present between powder and bullet, a dangerous pressure spike may occur which can "ring the chamber" or cause other forms of damage including personal injury.
Never intentionally load a small amount of black powder into a case which would create an unfilled air space larger than this distance. Black powder leaves more fouling in the barrel and chamber than smokeless powder. One hundred years ago the better grade of powders left a moist fouling which did not affect repeated shots too much and allowed many shots to be fired before the barrel needed to be wiped out. Current powders leave a hard dry fouling which will soon make it difficult to chamber another round and will also affect accuracy.
To combat this problem, special lubricants are available and the current thinking is that the lubricant must have NO petroleum products in it and will be made from all natural animal grease or vegetable materials and oils. Bees wax is also a common and major ingredient in successful black powder lubricants. Several commercially made lubricants have proven effective and many shooters mix up their own lubricants which work quite well.
To keep the powder fouling soft, target shooters use a short length of tubing to blow into the chamber after each shot. Moisture in the breath is absorbed by the fouling and allows many shots to be fired before a wipe out with a dry patch is required. Many advanced shooters have reported that they do not use the blow tube but wipe between each shot, thereby getting the very best repeatable accuracy.
Wiping between each shot is not always possible so you will see most shooters using the blow tube routine. Hunters usually have no need to blow moisture into the barrel since they rarely get more than one or two shots at an animal and therefore can wipe out the barrel properly after shooting. In humid weather one or two breaths into the blow tube may prove to be enough to keep fouling wet and soft.
On a dry hot day you might need breaths to keep things soft inside the barrel. Drink lots of water between blowing. This helps your breath to stay extra moist. The actual blow tube can consist of a ctg. Inserting the ctg. We want to keep the chamber walls dry and just apply humidity to the barrel portion.
If you intend to fire these cases in some other guns it may be smart to try your ammo in the other guns to see if they will fit properly.
If necessary, you can full length resize the cases back to standard size and fire form them in the next gun.
Once fire formed, keep your cases carefully segregated so they will not be used in another gun. Try new cases in your gun to assure they will chamber and full length resize only if necessary. This general advice applies to any other BP case which is almost a straight wall design. Cases which have a bottle-neck BN shape present different reloading problems and will usually require at least neck resizing for each reloading.
The BN cases are sometimes more difficult to obtain good accuracy from and beginners are advised to start with the straight wall cases mentioned in this text. Dies made to handle the common caliber will work OK for the , ,, and neck sizing operation and bullet seating operation. Just set the die so the case is inserted only enough to rework the neck area and not to resize the full length of the case body. Somewhat better case control and possibly a bit more resizing accuracy can be obtained when using the correct die for each caliber ctg.
But the die will usually produce ammunition of excellent accuracy when it is used for those longer cases. Since full length resizing is not normally required when cases are fired only in one rifle they will go back into that rifle without problems.
The full length sizing die can be adjusted to perform the required "neck sizing" on the longer 45 cal. The expander ball will do its job as well using the same procedures. The bullet seating die also can be adjusted to seat the bullet and apply a crimp if one is used in all the longer 45 cal.
The only reason you would need the actual proper 45 cal. Such fat cases will have to be full length resized and then can be fire formed in your own rifle. This same rule would also apply to "fat" cases of any caliber. You would have to get a proper full length resizing die to squeeze down those cases to fit into your chamber but once fire formed in your gun you would only neck resize thereafter. A fired or new case will have too large a neck diameter and the bullet will not be held snugly or in a straight alignment.
The case neck should be resized down to a little undersize for a distance equal to where your powder wad will be located. A special "neck sizing" die can be obtained from several die manufacturers or the above mentioned die used when set to just work the case down to the neck area. Then the neck is expanded using the expander plug to a size which will grip the seated bullet firmly but not so tightly as to change the bullet diameter. This operation also opens the case mouth into a slight funnel shape to allow easy entry of the lead bullet.
This funnel effect is called the "bell" or "bell mouth". The thickness of brass in the neck area will affect how much case "spring back" occurs and may require a larger expander plug than came with your die set.
As a general rule, the expander plug is made. Many ,, and brass have such thick neck wall dimensions that an expander plug of. If you are using a very light weight bullet for your caliber, it is usually necessary to apply a firm crimp at the case mouth in order to create some resistance and allow explosion pressure to build up properly before the bullet starts moving.
The reason is because the primer blast will start the light bullet moving before the main powder charge can get fully ignited. Accuracy will be poor unless the bullet gets a good stiff kick on the base which obturates it properly into the groove diameter of the barrel. Heavy weight bullets have enough weight to resist primer movement and usually don't require any actual crimp in the case mouth. This is another of the subjects worth experimenting with to see what works best.
Only trial and error can show you what is required for your bullet and case type. Because these cartridges are only used in single shot rifles there is no need for a crimp if the bullet is fitted firmly into the neck. In fact use of a crimp would create another variable since crimps vary with small case length differences.
It is well known that having no crimp at all produces the most consistent neck tension and accuracy so if you can get away without use of a crimp then do so and see what results you get. For this reason, it is advisable to size down as little as possible so that the expanding operation tends to work the brass as little as possible. Straight wall cases such as the , and others of this type do not require much metal working so the need for annealing the brass is reduced greatly.
Bottle neck shaped cases do require more metal working so they will tend to need annealing more often. Modern high power rifle cases need annealing quite often due to the extremely high internal pressures being produced but black powder produces far lower pressures and those cases can be reloaded many times before needing to be annealed. In addition to helping prevent splits and cracks, annealing does one other thing which is perhaps even more important to BP shooters and that is As a case neck tends to get harder its spring-back from the expander plug will change.
This changes the grip or tension applied to the seated bullet. If you start to experience neck splitting I would suggest replacing that lot of cases.
Annealing cannot properly restore the internal grain structure of the brass and you are going to be faced with unknown neck tension conditions in such aged cases. Use a common propane torch or similar low heat type of torch we don't want welding heat here. Work in a dimly lighted area so you can watch the color develop on the brass case. Have a container of water at hand which is deep enough to cover the entire case.
Apply the heat carefully until you can see a dull glow of red starting to become visible on the case mouth.
Immediately drop the case into the water bath to cool it. Never allow the case to become so hot that you cannot hold it with bare fingers at the base. Depending on your type of flame you should produce the dull red glow in seconds of flame application.
How often to anneal BP cases is something which has not been accurately defined. I have cases which have been reloaded as many as 75 times and yet never shown any signs of splits or cracks. I pay attention to neck tension as well and if a certain lot of cases start to show an increase in neck tension I think it will be time to anneal them all. With my modern high power smokeless powder cases I do anneal them about every 10 reloads.
If allowed to keep growing in length they will get too long to chamber properly and if you are applying a crimp, you will find that the longer case length produces a stronger crimp than does a shorter case length.
Use a case length gage or caliper to keep track of case lengths and trim them back to the desired length as required. As a general rule, the , , and cases should be trimmed after the first two firings and checked every two firings thereafter. These calibers do not tend to grow much once they are fired a few times. Among the many trimming devices available, the Lee company offers a simple economical device which can be hand operated or spun in an electric drill.
It works perfectly and reliably. The ,, and cases stretch a great amount during the first shots. The stretches so much the brass may actually flow into the rifling, causing great inaccuracy and problems. For this reason you MUST measure and trim the case length after each firing until this stretching calms down and becomes very small. New unfired cases should be initially trimmed back to about 3.
After this first firing, measure the case length and trim it back an appropriate amount so as to never let the case exceed 3. After repeated firing you will see that the case has stopped stretching much and the overall length can be trimmed to about 3. Bullet shape and length 2. Powder type and quality 3. Primer type 4. Powder volume and compression 5. Overpowder wad type and material 6.
Bullet lubricant 7. Case neck grip on the bullet crimp or no crimp as well as fit in case neck 8. Bullet position in relation to where rifling starts 9. Many more little things which are capable of affecting accuracy. While learning to reload for the BPCR, you have likely been shooting your reloads and have some idea of what the rifle can do in the way of accuracy.
To properly evaluate accuracy you must shoot at a paper target so you can measure the group size produced and thereby get a correct opinion as to whether or not a change in one reloading step was for the better or actually was worse.
Position your bullet in the case so it is in light contact with the rifling of the barrel. Use enough BP so that the bullet and wad will then compress the powder. Load and fire 5 rounds at a paper target and write down the group size. Add 1. The seating of the bullet and wad will compress this taller powder charge more than.
Fire the 5 rounds and note the group size obtained. Repeat the process of adding 3. When you have reached the point where the powder is compressed about. Almost every rifle will display a shrinking of group size when the powder charge gets to where that rifle likes it. You will find a certain powder charge volume and powder compression which produced the smallest groups. You can then work around that data by adding or subtracting 1.
Once you have determined the powder volume and compression which seems to produce your smallest group sizes you then turn your attention to the other items seen on the first list above, such as changing the location of the bullet back off the rifling. When working up a load remember this simple rule.
Change only one thing at a time and keep written notes of what you are doing! As you can imagine, many things can produce or contribute to such results and we offer a list of things which can usually be found to be the cause or involved in the cause.
Bullets too small in diameter, or much too large 2. Lead alloy too hard or too soft. Being too soft is the more serious problem as it can allow the ogive of the bullet bump up erratically causing unexpected flight paths. When too hard an alloy is used it may not allow the bullet to properly obturate into the groove diameter. Bullets too short for 45 cal. This would be 45 cal. Bullets having beveled base design which usually are not too accurate 5. Lack of lubricant or poor lubricant, allowing fouling build up 6.
Fouling or lead in barrel or barrel or chamber 7. Case necks too small in outside diameter for your chamber, and having inside diameter requiring too small a bullet diameter. Cases previously fired in your gun should be used when developing loads. Case length too long and metal has flowed forward jamming into chamber throat ball seat , leade, or rifling. Measure case length first.
Too weak powder charge may fail to fully obturate bullet into the groove diameter of the barrel. Too powerful a powder charge resulting in excessive muzzle velocity smokeless powder only. Too soft an alloy combined with high muzzle velocity and shallow rifling can cause the bullet to "strip" and not engage the rifling properly.
Inconsistency with powder charge volume, compression, seating depth, bullets weights, bullet crimp or other assembly variations. Black powder burning badly with variable pressures due to poor quality or deterioration of the powder caused by moisture or storage conditions. Primer inconsistency of intensity and flame. Notify Me when available. Add product to Wish List.
Let us help! Chat Now. Was the information on this page helpful? Yes No. Do you accept our terms and conditions? Need More Information? Update Your Browser Now! Own this product? Going to get "How To" in about any book on handloading.
Sent from my iPad using Tapatalk. More for Paper Patched loads but the how tos are the same for greasers also. Once you read a book with "how to's" you'll have a better idea of why generic "data" doesn't exist for BPCR. I would try an get load information for the firearm itself first and go from there. Depending on what BP substitute you use the difference can be substantial. Black powder does not have a wide variety of data.
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