Boolit Makers & Gentlemen,
I've been following this topic regarding the 77/44 it seems like forever. I've got a 77/357 tack driver shooting lead so I decided to get one in a 44. I've corresponded with Crusty Ole Coot and others so I took the bait and came up with good results. So for those still interested or thinking about getting one, here goes:
Slugged the bore = 0.4295
Boolit - LBT 280gr LFN Plain Base boolit that drop from the mold at 0.4335 with a WW alloy.
Gas Check - Pat Marlin's checkmaker using soda cans - these things don't come off and they look cool too!
Sized - 0.432 with gas check swaged on the plain base and Veral's LBT Blue lube
Powder - H110 Started with 20.0 gr and went to 22.0
Primer - CCI 350 Started to flatten at 21.5 grains and they are flat at 22.0. I will stop there.
Brass - Assorted
Crimp - Lee Factory Crimp Die
Velocity - I don't really know but based on data that I've gathered I'm guessing the 1600's.
Notes: Veral (LBT) builds a top quality mold that has spring roll pins. These may take awhile to break in. At first I thought I had a mold that dropped 0.440 but it was not closing all the way. Veral was very patient with me about my fussing and under close exam - one of the pins was very tight fitting so I fixed that and got perfect boolits - they drop from the mold better than any mold I've ever used. For my alloy I use 9lbs clip-on WW to 1lb of 50/50 bar solder so I can come close to Lyman #2. I may throw in a nugget of Rotometals Super Hard if Im in the mood to harden things up a bit more. I water quench the boolits then size and lube with Pat's gas check that same day. NO leading of the barrel occurred with 35 shots during the test.
First problems: Rolled a few of these and found they would not fit or cycle well in the factory rotary magazine. There are 2 solutions and I did both. First is trim the 44 mag case to minimum length and they will fit better but there still may be some hang-ups due to the molding/casting of the rotary magazine. Second was to take the mag apart and file just over 1mm of metal from the front of the mag leaving the feed ramp in tact. Then take a few thousands off the left side of the magazine (as it sits in the receiver) where the boolit itself will touch. Be sure to take out any casting edges on the metal and plastic. Be sure to flush up where the plastic meets the metal too. Polish everything off with a Dremel and rouge. Use very fine quality needle files to start with and keep inside corners slightly rounded. Put the mag back together carefully - can be a PITA until you figure it out. Now my cartridges with this 280 LFN cycle and feed very well. There is a 3rd option = When ordering the mold you can get the crimp ring cut slightly higher but that will make the bullet seat deeper in the case.
I set up at 75 yards to do this. My longer range had swarms of South GA swamp mosquitos that will bleed me out fast.
First 5 shots at 20 grains just sucked and I thought.. oh no, not another 77/44 dud.
When I reached the 21 grain load, the group started to tighten up significantly. Then when I got up to 22.0 grains of H110 I had a very nice group and noticed a bit of pressure kicking in. BUT... After the 3rd shot the barrel heats up and my groups start to string vertically. If I let it cool between shots it groups well. Sooo based on that I will lap the bore, then float the barrel. It fits very tight in that factory stock. I also installed some bolt shims previous to getting the load worked up. I did lap my 77/357 barrel and it will almost cloverleaf at 100 yards with cast boolits -gas checked the same way. I use JB Bore compound or superfine Clover brand grinding compound with the felt disks from Brownell's. I lapped the 357 bore with 350 passes with JB's changing the felt every 100 strokes. With Clover I stop at 200 bore passes and test. I do not fire lap. If anyone needs pictures of the magazine work, PM me with your email and I will send what you need to see. Regardless of the stringing, I'm happy with the results and love the 280 grain LBT boolit. I love Pat Marlin's PB gas checks too. They require an extra step compared to others out there but they have been very successful for me. I just bought a Henry All Steel 44 mag carbine and I'm going to see how it works out with this load soon. If anyone is interested in following that let me know and I'll keep you in the loop or if anyone has done this with a Henry, please let me know.
As you can see in the picture, the group will start to spread a bit when the bbl heats up, but overall - not bad considering what everyone has been through with these particular 44's.
280 LFN LBT w/ Pat Marlin gas checks
Modified Rotary Magazine