vadeer

I am reviewing a trajectory chart for powerbelt bullets. I have zeroed my gun in at 100 yds, but the chart zeros at 150 yds. (link is below)

http://www.powerbeltbullets.com/docs/balchart.pdf

Does anyone know of a chart that zeros at 100 yds or has a conversion formula?

Thx.

Paul L Mohr

I use a calculator like this one.

http://www.biggameinfo.com/index.aspx

You will need to know your aproximate muzzle velocity, the dia of the bullet and the Ballistics Coeficient. You might be able to the find the BC on the power belt website. You could also guess until the date matches the chart you listed above. Then start changing the yardages to your likeing. You will also need your sight height from the bore of the rifle.

Let us know what kind of powder you use and about how much. If you search the internet you can usually come close to the muzzle velocity of your load. The only way to really know is to shoot it thru a chrono. And shoot it at different ranges and actually measure the drop.

The site I listed has been pretty accurate for me though.

Good luck,
Paul

livbucks

I was confused by the chart too. According to the chart, my shots should be high at 100 yards compared to 50, I think. I sighted the gun in at 50 and when I tried 100 I shot in the same group. I am still confused about how this works because I got different results than I should have seen. Where is the gun sighted in at that was on the chart? Maybe I'm just not accurate enough to see what the difference is. My groups are around 3 inches, sometimes a little better. I shoot a flinchlock
I push 295gr HP Powerbelts with 80gr 777 out of a 26" 1:48 twist tube.

Turkeyhunter1

Livbucks, the barrel you are shooting the bullet out of is mainly for roundballs or conical bullets!! The stablization of a powerbelt is better in a barrel with a faster twist. I would suggest shooting a Hornaday 385 grain HBHP. I shoot that through my 1 in 48 barrel, and have consistant groups. I use Triple 7, fffg form. GOOD LUCK!!

livbucks

turkeyhunter1
I get really nice, round, consistent tears in the paper even at 100 yards so they have to be flying decently stable. I'm always open to new things. The only reservation I have is hammerin' sabots. Why do they make the sabots out of hard plastic instead of a self-lubricating nylon or HDPE (did I get that right?). I always thought a 1:66 twist was for roundballs.

Turkeyhunter1

Livbucks, As for sabots, I would not shoot them myself. You get plastic fouling in the barrel, which could build up after time. I guess you could clean in between shot's. I have found that powerbelts are the bullet for my gun's. It's just a preference thing. Good Luck!!

cayugad

A real misconception of the 1:48 twist is that they will not stabalize a sabot or powerbelt. That is not the case at all. Many 1:48 twist barrels are excellent sabot and powerbelt shooters. A lot of it is determined by the depth of rifling in the barrel. The PA Pellet .50 caliber flintlock was designed for just that purpose. It was made to shoot sabots and the bigger conicals such as powerbelts, with great accuracy. Yet because of the rifling it will not shoot roundball all that well. This is what I have learned from all my research on the rifle.

This is also the reason why some of the 1:48 twist rifles are outstanding roundball shooters and they do not shoot conicals or sabots very well at all. Again, it is in the design of the barrel. Many people manufacture the 1:48 twist so it will do a good job with both roundball and conical bullets. This is the case but if you truely question their owner, they will admit that it does shoot one much better then the other.

The Thompson Center New Englander for example. My friend's .50 caliber with 1:48 twist is an outstanding conical and sabot shooter. Roundball on the other hand are a lost cause with the rifle. My Renegade is just the opposite, a great roundball rifle but will not shoot sabots. Again, the design of the barrel.

As for plastic buildup in a barrel, as long as you clean your rifle with a quality gun solvent that is made to remove plastic, lead, and copper deposits and use a brass bore brush with that solvent, the buildup will not really happen.

txhunter58

I use this ballistic calculator: http://www.handloads.com/calc/

You will have to check the velocity with a chrony or "guess". Most of my loads are pretty close to a 100 gr blackpowder/pyrodex equivalent.

BC for powerbelts are as follows for 50 calibers:

245 gr. = .161
295 gr. = .186
348 gr. = .220
405 gr. = .257