As I said in an earlier post, I'm not very experienced with BP, but all this back and forth indicates to me I had better stick with round ball. I'm not interested in hunting anyway. Don't count on me for this group buy.
As I said in an earlier post, I'm not very experienced with BP, but all this back and forth indicates to me I had better stick with round ball. I'm not interested in hunting anyway. Don't count on me for this group buy.
Quote:
Originally Posted by M-Tecs
Thank you Sir for your comments, I appreciate them.Quote:
Originally Posted by M-Tecs
After studding bullets (all factory made HB are swaged) and boolits for 45 Colt (Remington made), 455 Webley and 38 Special, here are features I would like to have:
1. Distance from the beginning of front driving band, to the end of aft driving band, to be at least 75% of nominal boolit dia
2. Front and aft driving band to have sufficient surfaces
3. Rebated base
4. Boolit, when inserted into cylinder to protrude no more than .5”
5. Grease grooves; 2 or 3
6. Hollow base (HB)
Requirements 1, 2 and 3 are to make sure that boolit is guided straight; when loaded into cylinder chamber, and goes straight in the barrel when lunched forward by powder gases.
You mentioned that you are not satisfied with Big Lube boolits:
http://www.biglube.com/Images/DD-PUK...5_WEB_PROF.jpg
IMO, fairly large grease groove shouldn’t be problem. I guess problem is that noted boolit is short, and aft driving band is very small, so when loaded, it doesn’t take much to deform it and push slightly crocked. Well, result must be larger group than anticipated.
Since desired boolit weight is 250-255 grains, the only way to load it, without removing cylinder from revolver frame, is to have rebated base and protrusion of front end no more than .5”.
Because of above conditions, and to have sufficient contact surface between boolit and barrel, the only solution is to have a hollow base boolit.
Here is Mike Beliveau https://youtu.be/VVmYRePzoOQ?t=167 , shooting one of those top open revolvers, using Kaido 240 grains bullet (FY information, Kaido boolits have aft driving band reduced). Despite far from ideal rest, Mike managed to get surprisingly good 2.5” group. When he tested boolits using two Ruger Old Army revolvers, with Kaido 255 grains, groups were larger 2.75”-3.75”, see https://www.youtube.com/watch?v=DdauzEFXMNc and https://www.youtube.com/watch?v=LP_dwo2nThA . I know that to get more conclusive results, more revolvers should be used. But still, even that test is showing that top open revolvers could be quite accurate. To be honest, I would expect better results from ROA revolvers; IMO they are better made, and have solid frame.
So, why such large groups when shooting Kaido boolits from ROA revolvers? Well, I believe the culprit is constriction in barrel threaded area. Many revolvers have a such problem, and when shooting lead bullets using light to moderate loads, pressure is not high enough to obturate boolits, and result are large groups. Since black powder develops fairly low pressure, solid base boolit obturation is not possible.
Top open revolvers do not have constriction problem, their barrels are straight and uniform from one end to another. The remedy for solid frame revolvers is hollow base boolit, that will expand once it passes constriction. This works quite well, so even 38 Special ammo with HB boolits, could be used in conversion cylinders installed on 36 cal. (actually .375”) revolvers.
Final issue is what would be better boolit, 2 grease grooves, or 3? To be frank, I am not sure. The only way is to make prototypes and and test them. Unfortunately, that will have to wait. I cannot make molds, and Miha is very busy, so new molds will not happen anytime soon.
However, there is one possibility. I do have .455-265 Webley mold, and I am thinking about reducing boolit height on ,730-.735”. That will give me 250-255 grain boolit. With meplat about .300” dia, just about right for ROA. But, there is no rebated base. That one will be created by making some sort of swagging die, to bump two top driving bands on ,457” dia, and to reduce two bottom ones to .451” dia. Without going into too many details, here is how noted boolit should look like:
https://i.imgur.com/VkKraiQ.jpg
If this version shows to be accurate, I will suggest to Miha to go with it.
That o-ring is interesting .Quote:
Originally Posted by Onty
Do you have any references showing it being used?
Sent from my Pixel 4 XL using Tapatalk
No, I don't, and never seen somebody use it that way. I just designed grease grooves to fit 1 mm wide O-ring https://www.mcmaster.com/o-rings/oil...width~1-000mm/ . However, in some BP rifles, where the breech plug is, O-rings are used as a seal:Quote:
Originally Posted by Valley-Shooter
https://www.modernmuzzleloader.com/t...-pocket.15867/
https://www.traditionsfirearms.com/p...ech-plug-a1442
I'm going to go out on a limb here, and say the o ring is probably not a great idea. there may be a material that would work, but here we are trying to rapidly move a slug, engage rifling (with rubber....), and ... I can't see it sealing better than a greased wad, either.
I'd be willing to be proven wrong, if anyone wants to try pushing some at 800fps down a forcing cone and into the rifling.
Time to update this thread. I have to admit that, considering everything I learned through this and other threads (thank you all for participation and contribution), I thought that my latest boolit design with 3 grease grooves for 45 caliber C&B revolvers is close to optimum. I even contacted MP-Molds about making prototype mold. Miha is now tremendously busy, trying to catch up with backlog, so my idea is on hold now.
In the mean time, I was contacting some black powder shooters in my area, and learned that selection of black powders and their substitutes in our stores isn’t good. Also, there is no SPG lube, they just use those available for boolits using smokeless powders, or home made ones.
Unfortunately, there is no Swiss BP, Triple 7 and other better quality black powders or substitutes. And to get those from other states of EU is a nightmare. The only two available are are Czech Explosia VESUVIT LC and Slovenian KIK, certainly not on a par with Swiss BP or other better quality black powders available in USA. The biggest problem with VESUVIT and KIK is considerable fouling that requires frequent wiping. Since nobody wants to spend time on the range after every dozen or so rounds, wiping revolver instead of shooting, they told me to think about something better regarding bullet design then what is available now.
Taking in account everything I learned, I started thinking what could be done with another boolit design to address noted problems, and went back to first post and design our member 45 2.1. proposed (thank you Sir). Also, I recalled Big Lube boolit and started searching more about it. From what I found, looks like multigroove isn’t optimum design when fouling is the issue. In my search I found an interesting thread with post from late John Kort (aka W44wcf) https://www.cascity.com/forumhall/in...?topic=54292.0 . Although, this thread is not about boolits for C&B revolvers, but for those used in 44-40. However, it clearly indicates that for fouling issue, one big, long grease groove is better design than mulitgroove one, even when total grease groove length is the same. In that respect, John designed boolit 43-215C http://www.accuratemolds.com/catalog...catalog-anchor , and 177 molds were sold, indicating an excellent boolit design.
I was puzzled why big, long lube groove is better than multigroove, even when total groove(s) length is the same, when realized that, in order to get a good lubrication between boolit and barrel, big, long lube groove has better hydraulic effect. Of course, only soft lubes should be used, hard ones can’t work. I quote John Linebaugh “Bullet lube, anything that is soft and gooie. If it resembles a crayon, that's all its good for” https://www.johnlinebaughcustomsixguns.com/writings .
When talking about “hydraulic effect”, during acceleration of boolit in cylinder and barrel, soft lube behaves like water or oil, and longer is the groove, higher will be pressure on aft boolit driving band, and more lube will be pushed between boolit and barrel. That is exactly what we want; more lubricant will make less friction for boolit, but more importantly, more lube in barrel will make fouling less pronounced, easier to remove, and next boolit will push fouling out of the barrel. In addition, better lubrication will considerably reduce leading, if not eliminate it completely.
Considering all above, I designed this boolit:
https://i.imgur.com/wjRQnCn.jpg
Is this a good boolit, would my theory work, I am not 100% sure. The only way is to make the mold, cast boolits and shoot them. Before making final move, I would appreciate you input and suggestion.
P.S. I apologize for too large picture. Imgur use to be very fine website, and resizing picture was very easy. However, now they changed something, and I cannot resize it any more. Please PM me if you know solution. Thanks.
https://castboolits.gunloads.com/sho...22#post5453922
All active group buys are frozen
Due to the lack of movement the past couple years on ANY of the group buys it was determined we would freeze all current active group buys and any future group buys until such time the manufacturers are able to start producing custom molds.
CHARLES
NOE can do hollow base molds. May be worth asking if they could do this design
No where did I see how much room is left for powder in a ROA, 1869 or an 1858. A long bullet with generous lube grooves and a hollow base take up a lot of volume in a cylinder
So is this group buy dead?
All group buys are dead. This one really never got off the ground due to at least a half of dozen changes to the design.Quote:
Originally Posted by garbear
Quote:
Originally Posted by M-Tecs
Ive checked NOE and nothing in stock. I live in utah same state where his shop located. Im interested in a hollow base mold for my ruger old army. The other mold noe doesn't have current stock either