I have a CVA Optima .45 calibre in-line. I bought it to see how the bullets I swage will work when saboted in a ML. It has a 1:28 twist rate.

Last weekend I tried out some of my 200 grain .358 bullets. I found that in all but one instance they keyholed. I then tried some Hornady 200 grain spire points and had the same result. I was using pyrodex pellets, and shot 50 and 100 grain loads.

I've been told that the 200 grainers may be too long to stabilize in the gun, and that maybe I should be using shorter bullets. My bullets were 1.07 inches long, while the Hornadys were 1.04 inches long. I make a 165 grainer that is .92 inches long, and I should be able to make a 180 or 185 that would go about .97 inches.

Does anyone have any ideas on my problem?

/crackes nuckles

Sabots and Muzzle Loaders... yea I know a little. While I dont have experience with the .45 directly heres what I do know. It might very well be just be too much SD to be stabilized in your twist, if you have access to lighter bullets it would be worth a try but concider the following:

First step in diagnosing things is to walk down range and pick up your spent sabots. Examine them closely. They should look like they could be re-used except for rifling markings on the outside. 90% of the time I experience bad accuracy with sabots its because I'm shredding them. They look like a petal is torn off or that from underneith where it slopes towards the center, its torn in a half circle around.

I once tried a new brand of sabots and didnt find any down range! At least not for the first 50 freaking yards... Seems they were holding too tight to the bullet causing crazy bullet flight. They should be relatively close to your gun (throw one as hard as you can... you should find spent ones a little past that distance).

Ok I'll assume you find yours and they look good... if not theres your starting point.

Here is where my lack of .45 experience will shine. In the .50 cal's you have choice of TWO different bullet / sabot combos (this is where newbies go horribly wrong IMO): .429" dia (44 cal) bullets and .451" (45 cal) bullets. Specific sabots are made for each time, miss matching them causes all kinds of problems. Also, as center fire rifles like certain component combinations, front stuffers do to. Trying the different sabot / bullet combos offers more chances to gain accuracy. The .44's are usually not held as tight as the .45's, this I think is due to less plastic to deform between the round and the barrel wall.

Now how does that help you with your .45? I honestly am not familiar with sabot options in .45 but I am pretty sure they make a .40 and a .357 sabot, each something you can test. (I need to talk the wife into getting a .45 cal ML just to test this LOL, I'm curious).

Let us know what you find out next time you shoot it.


-DallanC

Could it be a casting problem. Lead not hot enough to fill the mold cavity without bubbles? Bubbles would create an unstable bullet. Try casting a few at a higher temperature and see if you get more stable bullets.
Another thing, the diameter of the bullet must be what is called for by the sabot maker. Check your bullet diameters.

Quote::

Hunting is EXCITING! Bolt Actions are BORING!!!! Don't Mix the Two!!

Anything that goes bang is exciting to hunt with. I even like the sound of a string go 'twang'.

Never bored and always ready to hunt.

I agree with Dallan on 2 points:

1) I believe that the legnth of your bullet is too long to be satbilized in the slow twist in your muzzleloader. Most .358 caliber rifles have a 1 in 14" to a 1 in 16" for the slowest. This is much faster than the fastest 1 in 24" that I am aware of in a muzzleloader.

The legnth of a bullet and its revolutions per second (RPS) is the main factor in how fast a twist is required to stabilize it. Weight is much less of a factor. As an example take a .243 caliber all copper bullet and attempt to stabilize it in a 1 in 10" twist .243 Winchester, it can't be done, you will need a 1 in 8" or a 1 in 7". Weight is not the factor the legnth is.

Try some standard weight .357 pistol bullets such as a 158 & 180 gr. These should stabilize. BTW in my handguns - .357 Mag , .357 Max & .35 Remington I use the Nosler 180gr handgun partition bullet with excellent results. Your velicity will be very similar to my .357 Max and below what I get out of the .35 Remington, and this bullet will hold together.

2) Check your Sabots. If they blow apart in any way you will be lucky to hit the broadside of a barn from inside the barn!!! I have used Wonder Wads on top of the powder with excellent results in both .50 & .54s with PRBs, Maxis, Sabots and Powerbelt bullets. My suggestion is to give them a try also.

I never thought to look for the sabots. I won't be able to shoot for a couple of weeks (a pesky moose hunt is coming up), but I'll put together some 165's and 180's and give them a try. AND I'll look for the sabots afterward.

popgun:

I'm a swager - not a caster - my bullets are jacketed and uniform, so that can't be my problem.

Another thing I was wondering about is if its possible that I wasn't seating the bullets squarely? The sabots are Hornadys and they are designed for .357 bullets, but I don't think .001 is enough to make them inappropriate. I'm using a tip on my ramrod that's designed for pointed bullets, so I don't think that's a problem.

Maybe I'll play with a twist rate calculator, and see if it can give me a weight (or length) that a 1:28 twist rate will stabilize.

Here are some links to a company that I have tried in the past. I was intrested in finding out if they would work in a Contender so I contacted Gerard and he was quite helpfull and very friendly. His site has a lot of great information in one spot. This info is very usefull all around so please look it over. I know that much of it doesn't pertain to Primitive Weapons but some information is as this thread indicates.

As I stated in the previous post stabilizing a bullet is a matter of reaching the correct RPS for the given legnth of a bullet. If the proper velocity can be reached for the twist of the rifling the bullet will be stabilized, if your velocity doesn't allow the bullet to reach its stable RPS teh bullet will keyhole and begin to tumble destroying accuracy and effeciency.

Here are a few links to a site that makes custom homogonous bullets for modern firearms.


www.gsgroup.co.za/cip.html - International bullet twist chart

www.gsgroup.co.za/faqb...twist.html - Bullet Twist Article

www.gsgroup.co.za/07faq.html - GS Custom Bullets FAQs

gscustom.co.za - GS Custom Bullets Home Page


Good luck with the new tests.

Subsequent to my earlier posts on this thread, I made some shorter bullets (168 grains), and when they didn't work, made a different type of bullet that was shorter by necessity (both 197 grain and 171 grain). I still met failure.

I searched the web to see if there was an alternate source of sabots to no avail.

I then decided to buy some 40/45 sabots and build them up some way to make them grip my .35 calibre bullets. Today was my first attempt. I used cloth patching that was .011 thick, doubled it over and wrapped it around the bullet inside the sabot, making effectively a thickness of .044, which with my .358 bullets should make a diameter of .402.

I set out with 3 bullet designs all set up in these sabots, and was met with universal failure. When I could find the impact points the bullets were all sideways.

I scrubbed that project for the time being, and proceded to sight the rifle in using Power Belt bullets, it shot like a charm.

I'm thinking of using something else to build up the inside of the 40/45 sabots. I'm thinking of trying something like liquid paper or nail polish. Any thoughts?

Are you sure that gun is a 1/28" twist?


-DallanC

Dallan:

I haven't actually tested it myself, but its marked on the barrel and in the literature, so I have to figure that's what it is.

Hey what happened to your avatar?

-DallanC

If you really want to use the 200 grain bullets perhaps your equipment will allow you to swage a 40 cal bullet that is a bit shorter.

MMP Sabots offers a 45/40 cal sabot for that purpose. www.mmpsabots.com/ I use their 50/40 sabots for my Savage smokeless muzzleloader and they seem to work very well.

I talked to a commercial bullet maker in Manitoba, and according to him if I want to shoot pointed bullets with these sabots in a 1:28 twist rifle they shouldn't have more than a 2 calibre ogive - almost blunt. Mine have a 4 calibre ogive, so I'm out of luck - unless I begin making handgun bullets.

I really like the CVA Optima rifle, so now I have some decisions to make.

Sell the gun, buy a new one in .50 Cal. and use commercial ammo is where I'm leaning, otherwise I'll be getting some new swaging dies.

Hey Rick, I also shoot a CVA .45 cal. with a 1:28 twist and mine is really accurate with the 195gr Dead Center Sabots from Cabelas with 100gr of American Pioneer Powder. Go to cabelas.com and take a look at them. The bullet it's self is .357 dia, looks like a ballistic tip nosler boat tail except it's all lead with a polymer tip and an orange sabot.