36 cal. maxi-ball

[capt jack]

Just bought a 36 cal perc. rifle from the classified section, with a 1 1/8" gm barrel , and I ASSUME that it will be in 1-48 twist . Been shooting BP for some time now , so I don't expect any difficulty with PRB.

I have an old TC mould for a 128 gr. , 36 cal maxi-ball and have cast some out of pure lead.

Has anyone here ever shot the maxi out of that twist in that cal.?? I realize, that with that long bullet , I will probable have to heat er up pretty good to get the RPM's up to stablize that bullet , but was just tring to see if it is a workable combo??

I'm currently shooting a alox lubed 370 gr 50 cal. maxi out of a 32 twist GPH barrel , and they are extremely accurate!!

Thanks in advance for any input. Jerry

 

[Runner]

They shoot good out ofmy 1-48 Bobcat, but I don't have enough experience with them to say much more than that. A coyote doesn't want to stop and look back at 150 yards if you have one on a 36 over 60 grains of powder!.

 

[Hunter66]

Running a hotter load won't stabilize the bullet any better if the twist is insufficient. It will destabilize the bullet more. A lighter load would work better. You can't change the rpm of a bullet by going faster it will still rotate 1 turn every 48 inches if it is a 1 in 48 barrel.

 

[rice1817]

I am going to have to disagree with you on that one. You can change RPM by speeding up or slowing down the bullet. RPM is affected by the TIME it takes to traverse the barrel length in given twist, as well as the twist rate itself. This is why it is possible to shoot light roundball loads in a fast-twist gun that would in theory be better suited to conicals.

 

[410-er]

If you experment try with and with out wad.A wad will help seal the gas behind the bullet and prevent blow-by.I have a 36 Seneca and best groups with out wad are 35 grs of FFFg giving 3/4".With wad 45grs of FFFg is 3/4".This is at 25 yds.Haven't tryed 50yds yet.

 

[Todd Rickard]

A TC .36 maxi mold sold on ebay a week ago for over $120.00. Must work fer something!

 

[19DEK50]

I am going to have to disagree with you on that one. You can change RPM by speeding up or slowing down the bullet. RPM is affected by the TIME it takes to traverse the barrel length in given twist, as well as the twist rate itself. This is why it is possible to shoot light roundball loads in a fast-twist gun that would in theory be better suited to conicals.

I’m going to have to agree with rice1817.

RPM is a function of time, rate of twist is a function of distance. Velocity determines the distance the projectile will go over a period of time. Therefore, the higher the velocity, the greater the distance the projectile will travel over a given period of time, and therefore increase the RPMs.

If the projectile is longitudinally balanced, increasing the velocity will increase its rotational inertia, and subsequently, its stability. As the projectile slows down from parasitic drag, its stability likewise decreases with the reduction in velocity and rotational inertia. That’s why a 1” group at 100 yds. doesn’t guarantee a 2” group at 200 yds., or a 3” one at 300.

My .36 cal. will give me a 0.6” group at 25 yds. with a 25g charge of 3F, but shoot it at 50 and it opens up to 1.75”. If I increase the load to 35g, the group drops back down to just over an inch at 50 yds. The increased velocity from the greater powder charge gives the RB more rotational inertia and stability (hence, accuracy) at the 50 yd. range.

This is all predicated on the projectile being longitudinally balanced. That’s why I’m very very fussy about having the RB sprue centered before starting it down the barrel.