Home Forums Reloading Bullet Casting Best velocity for a 1/20..

What seems to be the best speed for a .45/535gr bullet that's cast at 1/20? Soft I know,but are we looking at 1000 to 1200 fps? More or less....

PM EvilTwin or sharpsguy if for a BP rifle or equivalent. Very good guys and they know their stuff!

I have ran the 535 postell, and similar, to 1275 from my sharps rifles. The big boys running 45-100's and 110's crowd 1350 awfully hard.
I also run the 412263 bullet in my 405 cast from 20-1 at 1600.
Bullet fit and a good lube are really vital.

Well,here's the deal...I loaded them in a .458 Win mag with 42gr of 5744 to about 1600fps and received a 3 FOOT group of keyholed bullets @ 50 yards.I was looking for a practice load,but this ain't it......

Sounds more like a bullet size problem. However with that said 42 grs was probably giving you way more than 1600. Try backing that down to around 30-35 grs. Don't crimp them.

Yes, and make sure they are seating into the lands; the bolt should close fairly tight. You don't want 1-20 to jump too much as it will mash and deform at the front (steering) end.

The bullets were sized at .459 and the Chrony read 1589 to 1623fps on the avg. However they were seated like a conventional bullet with a slight crimp.
Might be on to something now....

Be sure you have a good flare on the case mouth before seating, if you shave a corner off the base you'll have problems doluxe also.
Before the next outing best to go into that barrel and mine all the lead and copper fouling out.

A good cleaning is always a plus.
Just so you know,most all my rifles have a cast bullet load and I've been loading for a number of years.I just never loaded this soft of a bullet.I shoot a lot of cast .30,8mm,.338,.458 WM,.404 Jeffery and my .450/400,however all hard cast.This one has been educational and proves bullet hardness make a big difference.

Well hang in there.
I was looking at data in the Lyman 48 and older freebee book from Accurate, and that load you tried was cruising right against the fire wall.
I'm still of a mind you drop back to 35 grs and things will be much more gooder. If you're worried about the powder , just take a 1/4 sheet of toilet paper, roll it and set it on the powder before you seat the bullet.
In my rifles the lyman postell and similar do much better seated away from the lands.
We shoot 20-1 bullets quite a bit in bpcr and moa groups at 1000 yds are attainable, and one hole groups at 200 are common.

Thanks...I'm not too worried about the rifle,it's a Ruger .458 Lott,very strong by most standards.I been told by several, the 1/20 bullets can be very accurate.

I may try the T-paper for effect..even tho that amount is the daily allotment here in Michigan.I think the car companies are adding it to the equipment list now.....

If shooting that load in WM brass, again, try to get the bullet to reach the lands.

The BPCR is designed for lead in its throating; an off the shelf sporter is not, and most throats are generously cut, especially so in Magnums, like the Lott.

Soft alloy needs support, especially from case mouth to ball seat, into the leade. Best to make it up front and the back can slug up and seal off blowby.

Hard alloys sized to fit the throat and fully supported are always best, but I think you can make it work.

SO,you think these may be too short?

No, not if they reach the lands.

If they don't reach the lands the bullet can tip in the chamber and throat, and an alloy that soft needs support more so than a harder one.

Worst case, if you recover a bullet that has to jump without support the land engravings are generally uneven when they hit.

Your not getting any leading are you? If not, reach the lands, use a little filler if you need to and you should notice an improvement at the very least.

Thanks for the help.I will try the longer length tonight.I would say I am nowhere the lands with this load.
Good ideas,Guys..another reason to hang around the 'Fire....rifle

Just for kicks, you might try to heat treat those soft bullets. That might straighten them right out.

I use an electric kitchen oven at 450 degrees for two hours.
The 450 should be just hot enough that your bullets don't begin melting so try one or two bullets first as guini(sp) pigs at that temp to make sure you don't accidently melt the whole batch. Oven temps vary so it is best to check before committing all your hard work only to see them all slump.

After the 2 hrs. of heat, I remove the bullets from the oven and immediately dump the bullets into a 5 gallon bucket of cold water with a soft towell in the bottom of the bucket.

I have tried sizing both before and after heat treating and it doesn't seem to make much difference to me. So, just to keep things easy, I'd size before heat treating and then again after to seat any gas checks and to apply lube to the grooves.

1/20 tin lead won't heat treat Rolly; just lead, tin and antimonial alloys with the presence of arsnic.(WW, shot)

My bad. I thought 1 in 20 had antimony mixed with the tin that did the hardening.

If it is straight lead and tin, you are correct ! Sorry for the mis-information.

NBD Rolly, just keeping the cornfusion in check!

If you're going to use a filler over the powder use something like polyester batting or kapok (out of an old life preserver) to completely fill the air space. You don't have to pack it in, just a fluffy glob of it to keep the powder back against the powder. I would let it protrude up into the neck so the bullet tamped down when seated to ensure complete filling of the air space. Try to keep it uniform for each cartridge. A "ball of TP" on top of the powder will act like a secondary projectile inside the case and may (probably) ring your chamber when it impinges against the base of the bullet. Arguments vary as to whether the impinging itself causes the ringing or the weird pressure spiking. I'm not making this up, it's been accepted by the cast bullet fraternity for decades now. I personally don't bother much with fillers anymore. I noticed that my accuracy statistics didn't improve enough to justify the added hassles of using them. Others are more dedicated to using fillers. To each their own!

Gary