Markesberry Polar Bear

[coaster]

Hello I'm new to your chat board. I have a question. I have an chance to hunt elk in Idaho in 2009. I own a Markesberry Rifle with a 1-26 twist rate. I have been shooting precision muzzloading sabot loads up until now and the rifle does very well with them. The rifle qualifies for Idaho hunting regs but the sabot load does not. When I called Precision they said that my rifle would not shoot non-sabot pure lead bullets (their conical any way) accurately because of the rifling groves and twist rate. I see by the Idaho regs that powerbelts are legal. Has anyone used a markesberry 1-26 twist with powerbelts? I would really like to hear about it and the preformance you get.

Any help will bring much thanks. I really don't want to buy another rifle for one state?

Thank You

 

[exMember]

You should be able to shoot a lead conical with that twist with no problem. The groove depth might be an issue, Powerbelts are .500 but expand when the powder lights up to fully engage into the rifling. I believe CVA uses .010" dept rifling in their rifles and they fit snug on a clean, oil free bore.

For elk and the lead series powerbelt. The 405gr Aerotip driven with 80-85gr Pyrodex RS should do very well. The Lead series 444gr flat point would be the better choice as theres no hollow point in the bullet. I'd start with 80gr and work my way up.

 

[coaster]

Thank you for answering so fast.

I have been using 777 and black mag3 will they work with the 405gr and 444gr power belts? I like the black mag3 very clean powder.

Thanks Again

 

[exMember]

Yes they will work, I'd go with the black mag3. I believe it is quite a bit hotter than pyrodex. Maybe equal to triple 7 so when i say use 80gr pyrodex max, Triple 7 users need to cut it back 15% (Or 10 grains to make it easier) to be equal with Pyrodex RS.

The 444 is where i would start and fiddle around with some charges.

 

[coaster]

I'll take 777 and Black Mag3 to the range with both the 405gr and 444gr the next chance I get and see what they do. I have a chronograph so I will post velocity and accuracy (shooting from a sled that will take the me factor out for accuracy. Maybe this will help someone in the future. It may be a while before I post. I need to order the bullets first. I've got plenty of time before 2009.........

Again, Thank You

 

[exMember]

Sounds good but just remember, The powerbelt bullet is pure lead, very soft and you can not hot rod it like you can do with the modern sabot pistol bullets. If you have easy access take a 12x12" box and fill it with sand and when you start off with the charge, empty the box and remove the recovered bullets and this will allow you to see if you are pushing it to hot or if its just right. Check out the Recovered Powerbelt area on the forum to see the good vs the bad.

 

[coaster]

My main purpose for this load is open sight Idaho legal load. I am not a long range open sight shooter at 57 yrs old these eyes need to be inside 125 (deer)to 150yards(elk)(the only reason I say this is becuase I own a 32 win special open sites and these are my range limits). That being said I want a load to be as accurate as possible. I think load accuracy helps to negate some of the aging eye syndrome I want accuracy, good penetration, and energy on elk size game inside 150 yard max. I think the sand box will be hard to accomplish at my range but we will see. What velocity, using my chronograph would start to push powerbelts beyond their performance range? The area that I will be in in Idaho next year is very thick and long shots are rare. Most shooting will be inside 100yards.

Thanks

 

[exMember]

I cant help with FPS and such as i am not in to that kind of stuff. With the 405gr and 80gr charge i sight dead on @ 100 and an only 5" low @ 150. The 444 i'd say its safe to use 90-100 to maybe even 115 grain Pyrodex RS. The 444 is a big bullet and can take a stiffer charge thanks to the bullet not having a hollow point bored into it.

 

[VAKnight]

This is not going to be a speed demon round.

You can count on velocities in the 1200 - 1400 fps range with these loads. Off memory, the Powerbelts in this grain size have a ballistic coefficient of about 0.25.

That means (for 1300 fps):

A 50 yard zero is down 4.5" at 100 yards, and down 15.8" at 150 yards.

A 100 yard zere is up 2.2" at 50 yards, and down 9.1" at 150 yards

A 150 yard zero is up 5.3" at 50 yards, and up 6.0" at 100 yards


The energy at 1300 fps for the 405 grain is:

50 yards - 1309 ft.lbs.
100 yards - 1142 ft.lbs.
150 yards - 1020 ft.lbs.


The energy at 1300 fps for the 444 grain is:

50 yards - 1434 ft.lbs.
100 yards - 1252 ft.lbs.
150 yards - 1119 ft.lbs.


My advice is that you need to understand, that with a load like this, you are now in the area of old west 1850's hunting technology...ie. big lead low velocity. The 444 would probably give you a better depth wound channel due to mass size kenetic energy. Either one should do the trick.

Now for sighting in and hunting, do not be suprised if your "happy rifle" load has a lower fsp than above when you chrono it. Pay a lot of attention to that and the ballistics tables. In this velocity range, if you go down only 100 fps (to 1200 fps), you will loose 1 - 3" of trajectory at 150 yards.

My advice, unless you are very good at range estimates and hold overs, would be to zero at 100 yards and keep your shots limited at 125 yards. That should keep you in the "kill box" for elk.

Hope this helps.

 

[coaster]

When I get to the range I will post results. Lets hope the Markesberry polar bear has a happy load without the sabot. You folks are great.

Thanks Again