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ktw
04-16-2006, 02:33 PM
I'd like to work up my first cast load for a rifle.

I have a 243 that I don't use much anymore. This is a tang-safety Ruger M77 ultralight I bought over 20 years ago when I was stationed out in the high desert of S Cal. Used it as a carry-all-day, coyote/jack-rabbit rifle. Haven't gotten much use out of it since moving back east. Still like the rifle, just not a big fan of the 243 for eastern deer hunting. Looking at it on the rifle rack the other day I figured I was going to have to a) re-purpose it, b) rebarrel it, or c) sell it.

I could use a mid-range (50-200 yard) plinker. Something cheap to shoot, but less sensitive to cross winds out past 75 yards than a 22lr. Figured I might try loading this rifle, as-is, down to 22-hornet performance with a cast bullet.

In looking at the rifle bullet molds available, it appears they fall into two main styles; the Loverins and the Boreriders. Can someone provide (or point me towards) an explanation of the strengths and weaknesses of these two designs?
Which style is more suitable for the purpose stated above, given the rifle in which I plan to use them?

-ktw

9.3X62AL
04-16-2006, 02:45 PM
KTW--

I have come to a similar conclusion about the 243--not quite enough for deer except under ideal conditions, and a pretty nice varmint caliber. I've used the RCBS 95 grain castings with 12.0 x 2400 and dacron to shoot a LOT of 5 shot 100 yard groups at or under 1.25", and won last year's NCBS group match with a 1.02" cluster.

I don't weight-sort boolits, but I do a pretty "scorched-earth" eyeball sort-out. You need to be pretty unforgiving with these skinnier boolits.

I also tried some samples of the Lyman Loverin design, and they shot almost--but not quite--as well as the RCBS bore rider did.

Harking back to your desert experience, the RCBS boolits DO IN jackrabbits with finality. The loads above prompt about 1700 FPS from the Rem 788, and Carpetman has gone a lot faster with his castings in this caliber.

StarMetal
04-16-2006, 02:59 PM
I agree with cast bullet use a 243 is not a good deer round, but with jacketed it's subperb.

Joe

Maven
04-16-2006, 03:13 PM
KTW, In principle both bore riding and Loverin designs should shoot equally well IF they fit the throat and bore of a given rifle. In practice unfortunately, they may not. E.g., I have a Ruger #1 in .243Win. that will put 10 jacketed bullets (80 - 87gr.) into 1" @ 100yds. with suitable amounts IMR 4350 or IMR 7383. Cast bullets won't do quite as well, but will group into 1 - 1.3 m.o.a., albeit at much lower velocity. Unlike Dep. Al and Carpetman, I never was able to achieve that level of accuracy with either the 95gr. (Lyman) or 105gr. (RCBS) bore riding bullets and have since disposed of both molds. The Loverin design (Ly. #245496), however has given me the performance I mentioned earlier, but sized to .244" (as were the bore riders) and held to ~1,750fps. Additionally, the Ruger #1 is very fussy about OAL with this particular CB. Your #77 may have similar foibles.

Btw, Col E.H. Harrison complained about the too small nose section of bore riding designs in his NRA-published book, "Cast Bullets." We've also bemoaned the lack of fit on many off-the-shelf molds on this board as well, whcih may partially explain the number of custom mold designs offered in the "Group Buys" section.

Newtire
04-16-2006, 07:29 PM
I'd go with the Loverin design in the .243 simply because it is shorter in length and you won't have to seat it into the powder space to get it to work. Depends on length of throat too. Have the Lyman 245498 and it's alot of long nose with not all touching the lands. Maybe this design I have would work better in the 6mm Rem. with it's long neck case.

ktw
04-17-2006, 02:26 PM
Thanks to all for the replies.

I guess the first thing to do is get a good cast of the throat area in order to see what I've got to work with.

Can someone with either an RCBS 243-095-SP mold or one of the Lyman 245xxx molds take a few meaurements and let me know what I can expect as far as as-cast nose/driving band diameters (ACWW alloy)?

Wasn't looking to do any hunting with this rifle. Have plenty of other rifles for that. Just looking for a cheap, light practice load. I would be satisfied with one that gave me 2 MOA or better out to 200 yards.

-ktw

Newtire
04-18-2006, 08:57 AM
Thanks to all for the replies.

I guess the first thing to do is get a good cast of the throat area in order to see what I've got to work with.

Can someone with either an RCBS 243-095-SP mold or one of the Lyman 245xxx molds take a few meaurements and let me know what I can expect as far as as-cast nose/driving band diameters (ACWW alloy)?

Wasn't looking to do any hunting with this rifle. Have plenty of other rifles for that. Just looking for a cheap, light practice load. I would be satisfied with one that gave me 2 MOA or better out to 200 yards.


-ktw
Hi KT,
Will get you the diameters in tomorrow's E-mail for the 245498. Got to get to work right now. Have a bunch cast up but can't get to it right now.

Newtire
04-19-2006, 08:43 AM
Ok..Here are the specs from my mould I bought off E-bay. It's a 245498 Lyman, cast from Hardened WW.
Bullet length w/Hornady gascheck=.957"
Diameter on all lands=.245"
Diameter just ahead of front land=.232"

Can't tell you how they shoot yet as we haven't had alot of days without rain and none free on weekends yet.

HORNET
04-20-2006, 06:56 AM
ktw,
You can only rarely go wrong getting a short-nosed Loverin design that's in the middle of the weight range for the caliber. You can run softer alloys (more appropriate for hunting) faster with less sophisticated lubes than you can use with the bore-riders and they can generally be sized to handle a wider range of barrels without things getting wierd.
On the other side, bore-riding designs usually have better ballistic coefficients and may be slightly more accurate if the dimensions match the barrel properly. Bore riders have less detailed designs and are easier to visually inspect for defects.
You pays your money and you takes your choice.:bigsmyl2:

ktw
04-20-2006, 10:01 AM
Newtire: thank you for the measurements.

Hornet: thank you for the loverin/borerider advice.

-ktw

9.3X62AL
04-20-2006, 01:13 PM
KTW--

My RCBS castings run .2455" on the drive bands as cast, and the .244" sizer gives them about .2445". The bore rider portion is .239", and it has light engraving on the lands of my Rem 788. Alloy used is Taracorp 92/6/2.