OAL for Cast 8mm

[tkcomer]

I bought some cast bullets from Hunter's Supply for my 8MM Mauser. 170Grn flat points. If I seat to the crimp groove, the OAL is only 2.611. That seems awfully short. I've measured and weighed the bullets. That's within spec. But still, a 160grn bullet from the Lyman mold should have an OAL of 2.73. Their 181grn mold has an OAL of 3.010. Max OAL is for anything is 3.250. Are you supposed to seat these flat points that short? Seems like a long jump to the lands. If the bullet is barely in the case, it's OAL 3.012. This is a new round for me and I'm planning on shooting low power loads using Unique. Just not sure it should be this short. Thanks for any replies.

[Blammer]

I'd load them to standard OAL and see if they function from the magazine. If they do, shoot away.

[tkcomer]

They cycle through the magazine just fine. I'm thinking the fact that they're flat nosed is why they are so short. Like I said, if I barely stick a bullet in the case, they only measure 3.012. Just trying to figure out if others have shot similar bullets with that much jump to the lands with a low power loads.

[BoolitBill]

I have shot a Ranch Dog flat point that was meant for the .32 win special in the 8mm mauser. I seated it in the top seating groove and it shot fairly well. Later I found that seating to the second lube groove gave me a little better accuracy but not a lot better. I just load to the top seating groove now as it is easier. Yes it does make a short looking cartridge but it cycles from the magazine just fine and for plinking with low power loads it shoots good enough.

[Bob Krack]

With my CRS, I'm a thinking the most important issue with OAL is mostly concerning how much of the projectile is taking up space in the "boiler room".

Many can remember much more and lots that I forgot.

Bob


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[tkcomer]

That's good to hear. I was worried I'd get leading from that long a jump. It's a flat base bullet. I was hoping Hunter's Supply knew what they were doing when they put the crimp groove where they did. I'll load 10 to the crimp groove and see what happens. This will be the first time out with the K-98.

[Bob Krack]

That's good to hear. I was worried I'd get leading from that long a jump. It's a flat base bullet. I was hoping Hunter's Supply knew what they were doing when they put the crimp groove where they did. I'll load 10 to the crimp groove and see what happens. This will be the first time out with the K-98.
Keep us updated, I want a little archival information for when I buy a mould for my Turkish Mauser (8x57).

Bob


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[tkcomer]

With 14grs of Unique, absolutely no leading. That's the good part. The gun was shooting way left and scattering bullets the first 4 rounds, but seem to tighten up the more I shot it. But I only shot 10 rounds as I was checking for lead in the bore. I drifted the front sight and the last two shot about 5” high at 25 yards, but were 2” apart. The next step is to try 13grs of powder and put my stick on dot at the lower part of the paper and try to get an idea of what this gun is doing. That first 4 shots were about an 8” group. At 25 yards! And I'm not going to clean the gun. I want to see what it does dirty as those first 4 were all over the map.

[darthdave22]

What is the condition of your barrel out of curiosity, I recently bought a VZ-24 mauser with a very typical semi pitted barrel and strong rifling. I havent gotten a mold yet Ive just been shooting junk steel surplus. I was kinda wondering if the lead would tear up on the pits a little bit. I am planning on hand lapping it at some point but I havent gotten around to it. Seems to me i read somewhere that the lead can fill up the pits a little for better acccuracy ??? that sounded dumb to me though makes little sense.

[tkcomer]

I'm not for sure yet what's going on. I've only fired 10 rounds. The barrel has no pits and the rifling is sharp. I've loaded the next 20 bullets to just above the first lube groove. Just a slight kiss from the Lee Factory Crimp Die to remove the bell. 2.746” is what that comes out too. Still way short from the max OAL. We'll see how these do with 13grs of powder.

[Shiloh]

To fit the magazine. Id be curious as to how long the throat is of your particular variant.
See what long cartriodges do loaded singly.

SHiloh

[tkcomer]

Well, test results with 13gr of Unique was disappointing. I can't keep the bullets on a 11x8” sheet of paper at 29 yards. No consistency whatsoever. The last time I had this problem was with a Rossi 44 mag gun. It would shotgun .429 plated bullets. Bought some .431 bullets and it was good to go. There is absolutely no leading in this gun. Bore is shiny and grooves are sharp after the 20 round test. Not sure what direction to go. Any ideas?

[excess650]

Keep us updated, I want a little archival information for when I buy a mould for my Turkish Mauser (8x57).

Bob


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My Turk ia a 1944 K Kale large ring 98. The groove diameter seems to be .3255" and bore closer to .313, but the throat is worn. The group buy 326407 185gr(?) is a good bullet. I also have a Mountain Molds that I designed at 225gr and the Lee Maximum nominal 235gr(?) that weighs closer to 250gr. I seat 'em to just engage the rifling. So far my best load is 18gr AA5744 in RP cases with F210 primers under my 225gr. Its consistently sub 1" at 58 yards with iron sights, and quite often closer to 1/2". Its a moderate load, but accurate and consistent!

The Lee "Maximum" is avialable from Midsouth on the "sppecial order" list. My double cavity cast very well, and definitely lets you know its been fired when loaded over 35-37gr AA4350 in RP cases with F215 primers.

The group buy NOE 326407 seems pretty sporty over 26gr AA2015 in RP cases with F215 primers.

I seat my bullets to just engage the rifling, and do not crimp. These all work from the magazine, but the NOE 326407 feeds the best as it has the smallest meplat.

[Bob Krack]

My Turk ia a 1944 K Kale large ring 98. The groove diameter seems to be .3255" and bore closer to .313, but the throat Very interesting. Mine is also a '44 K Kale large ring but I believe mine is the variant called "large ring small barrel".
Thanks
Bob

[tkcomer]

I'm going to try backing down to 10grs of powder. If the bullets are too small. Maybe they'll get a grip at the slower speed. Though if they are scooting down the barrel, the lack of leading puzzles me.

[tkcomer]

Well, I tried the 10gr loads at 33 yards. Better, but still wildly inaccurate. You can see the results here: http://www.pixagogo.com/5724124248 The last two went under the box. STILL no leading whatsoever. But now I see powder flakes in the barrel. I was able to keep most on the paper this time. Should I go to 9grs of powder? Or should I bump them up to max and see what they do?

[tkcomer]

I've been given advice all over the map on these bullets, but one guy said these rifles tend to have the throats shot out of them. That, coupled with the long jump to the lands means I need a bullet 2 thousands over. 1 thousands won't cut it. If that is true, is there an unchecked .325 mold out there? I've "heard" unchecked bullets don't do so well.

[Dutch4122]

I've been given advice all over the map on these bullets, but one guy said these rifles tend to have the throats shot out of them. That, coupled with the long jump to the lands means I need a bullet 2 thousands over. 1 thousands won't cut it. If that is true, is there an unchecked .325 mold out there? I've "heard" unchecked bullets don't do so well.

Contact Bruce at BRP Custom Molds. He is one of the vendor sponsors here at Cast Boolits. One of the boolit designs he produces a mold for is the old Group Buy .327-180-GC design. These drop fat enough so that you can size them to the desired diameter for your rifle.

A quick way to find out what diameter you need with these old milsurps is to measure the inside neck diameter of a casing fired in that rifle. Then size to .001" under that diameter. Example: if the inside of the case neck measures .326" then you need a boolit that is sized to .325." Don't be surprised if your case necks measure even bigger than the example, as many of these old chambers were cut fat.

Once you have the proper sized slug for your rifle, make up a dummy round that is just started into the case neck and slowly/carefully chamber it in your rifle. Extract the round carefully and see what you get. As long as this dummy round is not too long for the magazine box you will be in business. Then just seat the loaded rounds to the same OAL as the dummy and give them a try. I think you'll be much happier with your accuracy.

One of my favorite loads for this boolit is 15 grains of Unique with a CCI large rifle primer.

Hope this helps,

[runfiverun]

plain based boolits do fine at lower velocities, 1600 and under, my best luck has been about 1400.
you could be seeing erratic ignition with the lower load volumn also.
generally fitting the throat is going to be your best bet on getting any type of cast boolit to shoot well.
i'd go back to square one, and raise the muzzle before each shot.
if that helps then you at least know what to work on.
the oversized will help also but not as much as filling the throat area to begin with.
a longer boolit will also provide more bearing length in the bbl.
i have seen some rifles shoot two designs that were very similar but one had more bearing length vastly differently.

[tkcomer]

I loaded 20 rounds with the 10gr load. I need trigger time also. Some seemed pretty weak. One was so weak that if I hadn't seen the mud fly, I would have pulled the bolt looking for a stuck bullet. Inside case diameter of most is .323. Found one at .321. But that was from the 10gr loads. Not sure if that is enough pressure to blow them out. One thing I am going to do is buy FMJs my next order. I want to see what the gun does with those.

[tkcomer]

It's official. These cast bullets aren't going to do good through this gun. You can see the results here:http://www.pixagogo.com/5724124248 It's the last three at the bottom. Click on a pic to make it bigger, then click on original at the top to blow that up. I tried bumping up the load to 15grs Unique. Wildly inaccurate. Then I tried my new powder I ordered, 12grs of Trail Boss. Still inaccurate. But I kinda like this stuff. Fills the case up and it seems the kick was less sharp than Unique. Then I tried 12grs of Trail Boss with 198 Privi FMJs. I was kinda disgusted by this time so I didn't really try that hard, but eureka, the gun printed a group. The only bad thing is, the front sight on the gun is already drifted way left. Not sure I can correct this. I'd be afraid to drift it further. Just thought I'd let the gang in on my results.

[PAT303]

I shot my Turk this morning with Lymans 324366 mold and Lee Maximums over 14grns of Trail Boss with Lars lube and gas checked and the 366's shot a couple of 2'' groups but the Lee shot 1'' easy.The big Lee slug is a winner in two K98's I've shot it in. Pat