Author Topic: Cast Vs. Jacketed  (Read 729 times)

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Offline BrushBuster

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Cast Vs. Jacketed
« on: November 23, 2003, 06:22:32 AM »
I have a novice's question to ask as I try to quickly get educated on cast bullets:
Assuming I have fitted my cast bullet to the barrel properly, and have purchased (not cast) the right bullet for the purpose; what different reactions in recoil, pressure and velocity would I expect in comparison to my favorite load using the same weight and shape jacketed bullet?

I'll try to be more specific:  For the jacketed bullet, 32000 cup.  Barnes 250 grain FN,  2300 fps.   60 grains of ReLoder 19,  .348 Winchester calibre. WLR primer. (everything except the bullet the same)

What would be the difference if I had the equipment to measure differences?
Struggling every day, to hold onto what I took for granted yesterday.

Offline Johm D M

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Cast Vs. Jacketed
« Reply #1 on: November 23, 2003, 04:44:47 PM »
Slightly faster velocity for the first shot and major clean up or pressure indicators for the second. Most commercial lubes would be designed to handle 16-1800 fps in a rifle. Recoil is an indication of psi and bullet weight and would be similar.

Offline waksupi

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Cast Vs. Jacketed
« Reply #2 on: November 26, 2003, 06:08:22 PM »
For the caliber and velocity, you can match these easily with cast bullets. Use a good lube, like Felix,  LBT Blue, or Tom Grey's mix, and you will have the velocity and accuracy you are accustomed to. I use Felix, and shoot several chamberings in the 2250-2500 fps range, including Hk G3 class weapons, with no leading, and good accuracy. No fouling in gas ports, either, by the way.

Pressures would be less, as cast bullets are "slicker" than j!%@%ted bullets. You may need to temper the bullets, which is easy, even if buying commmercially, or ask for a Brinnell of at least 22 from the vendor. It's probably better to ask for harder if possible, because they will soften with age unless stored in a freezer until you are ready to shoot them. Then check the hardness when you get them, and the diameter. 22 Brinell should take you up to the 2500 fps range with a properly fitted bullet and good lube. Anyone telling you  that these velocities aren't possible with cast haven't shot them much. I know of posters on this page that will take your bets up to 3000 fps, and happily take your money home with them in various calibers.

 This chambering will handle a velocity of at least 2400 fps with out leading, and good accuracy, assuming proper bullet size. I imagine if you dropped on down to Veral's page and asked him, he would most likely tell you, you can shoot at velocities with cast that will scare your shoulder! Actually, with a good lube, you could very well surpass factory specs by several hundred FPS, with no extreme pressure signs.

Offline felix

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Cast Vs. Jacketed
« Reply #3 on: November 28, 2003, 04:45:38 AM »
Perhaps the best thing about cast boolits is that they can be more easily manipulated to fit the gun.  This means the diameter can be adjusted to fill the case neck to its maximum limit, that is, so the case neck area still slips into the chamber with very little slop, like for a 0.001 clearance. ... felix
felix

Offline BrushBuster

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Cast Vs. Jacketed
« Reply #4 on: November 28, 2003, 05:55:01 AM »
Okay Waksupi, In future I'll try not to use the J%$^&**d word. Question: I have been told by a pro. caster that the number of lube grooves on a CB design is not as important as the quality of the lube used. Do you agree?
I ask this because I was inclined to turn down a bullet I liked for one that had more grooves.

Felix, I have recently learned that the chamber-bullet fit is far more critical to accuracy than the minimum bore dia. Your post confirms this, now I would like to know how to determine this; is it done by slugging the chamber? Also are you the same guy that has lube named after him?
Struggling every day, to hold onto what I took for granted yesterday.

Offline felix

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Cast Vs. Jacketed
« Reply #5 on: November 28, 2003, 06:16:47 AM »
Yeah, I'm the lube guy. A chamber cast would be great to have for sending that casting to a custom mold guy so he can shape the nose properly.  Other than that, it is just better to find the largest boolit that will fit, and modify the alloy for the powder charge.  For example, some loads like a harder boolit, and other loads a softer one.  It has to do with how that boolit gets started down the bore without cutting itself to shreds, or distorting itself enough to let gas escape around its diameter.  Harder boolits can be fitted tighter without detriment.  This kind of "crap" is the hobby part of the hobby and becomes the ultimate challenge when making a gun shoot.  Some pretty bad bores can shoot cast a lot better than they can shoot a condom, and it's up to the user to find that magic combination. The only time a gun will not shoot straight is when its barrel changes dimensions along its length.  A gun having a choke wider than cylinder is pure trash and will never be made to shoot cast or condom correctly. ... felix
felix

Offline waksupi

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Cast Vs. Jacketed
« Reply #6 on: November 28, 2003, 06:43:49 PM »
Most bullets have more lube grooves than they need, considering the good lubes we now have. There are a lot of single and double  groove designs that will shoot just fine.