To gas check or not

[parrott1969]

To check or not to check that is the question. I am giong to order a mold for a 44 mag and I am trying to decide on a checked mold or plain base. This is going to be for a pistol and a handi rifle. I generally load toward the upper limits so which way should I go?

[Themoose]

If you are going to load "upper limits" I think that you would want to go with gas checks

[Ben]

If you've got the proper bullet fit, and you're shooting reasonable loads, ( Sub Max ), you'll do just about as well with a good plain base design as you will the g/c design.

The Lyman 429421 is a fine plain based design for the .44

The RCBS 250 Keith plain base is another fine design.

There are others ...........

Ben

[harrya]

I've got a question along these same lines: Do you HAVE to cap a cap designed base mold or can you use it non-capped for lower limit loads
harrya

[RobS]

If you've got the proper bullet fit, and you're shooting reasonable loads, ( Sub Max ), you'll do just about as well with a good plain base design as you will the g/c design.

The Lyman 429421 is a fine plain based design for the .44

The RCBS 250 Keith plain base is another fine design.

There are others ...........

Ben


+1 on this............assuming that your 44 has proper cylinder throats to groove diameter (preferred .001 cylinder throats over groove diameter or a bit more) and no constrictions in the barrel. Even cylinder throats that are the same as the bores groove diameter should be ok, but not ideal for cast boolits. If you plan on shooting max loads and your gun's bore and/or cylinder throats are not designed correctly then you'll be better off with a gas check design.

Regarding the Lyman 429421 vs the RCBS 250 KT I would go with the RCBS as Lyman as been a little relaxed on their quality control efforts and many people are getting molds that cast undersized. Some people have had good experiences with Lyman in the past month or so but if it were me I would still go with the RCBS as it is more of a Keith design with the lube groove being a flat bottom design and it will hold more lube vs the Lyman. Lyman does make good molds when they leave the factory with the correct dimensions.

[RobS]

I've got a question along these same lines: Do you HAVE to cap a cap designed base mold or can you use it non-capped for lower limit loads
harrya

You stated to cap or not cap a cap designed bullet...............I believe you are asking to gas check or not gas check a gas check designed bullet. If a woodchuck could chuck wood :-P.

Anyway there have been people who have had good results by not gas checking at lower velocities and then they can also gas check if they want to push higher pressures/velocities. My experiences are limited, but I've done it and accuracy was decent at the lower end, but the middle end was not good so I would end up gas checking from mid load and up.

I say get a plain base design if your gun is built correctly as I mentioned in the above post. If you gun has a few hiccups or you don't want to have to work as hard on load development then a gas check design is probably a better option for you. Gas check bullets are easier to get to shoot well if things are not in order so to speak.

[harrya]

RobS,
Thanks, I didn't make myself very clear and you did a good job of cleaning things up. Specificly, 308 @ 115/150/180 gr. mouse loads 5 grs powder and under. Mid loads and up would be gas checked.
thanks much
harrya

[fecmech]

I have had excellent results with the Lyman 429421 and have run it up to 1400 fps out of a Super Blackhawk. Groups run 2-2.5"@ 50 yds and I don't think that's too bad. You will pick up 300-400 fps over a revolver with your Handi so if you want max speed out of the rifle you probably want GC. That said GC's are a pain compared to PB bullets and a heck of a lot more expensive. Also if you slow the Handi down in the 1500 fps range PB would probably work just fine for hunting. Your call but I've gotten along just fine without GC's in both the .357 and .44 mag.

[RobS]

harrya

I don't know about a 308 with 5 grains or under powder...........I've never heard of anyone doing this, but maybe there is someone here who will chime in.

[parrott1969]

Thanks guys, I still have a lot to mull over.

[lwknight]

I can't see that leaving the gas check off would be any different than using a bevel based boolit. Pressure lubing is a problem without the checks on bullets designed for checks.

I use the LLA for low end stuff and have had good results with my 429215 without the checks.

[MJR007]

You will end up with one of each...

[Jack Stanley]

If you are going to run near the top most of the time stay with the flat base and make it fit what you're shooting as good as you can . I use bullets designed for gas checks up to almost plus "P" loads in a thirty-eight cases with good results . Also in low velocity rifle loads with excellent accuracy so the is hope for some kind of shooting .

Jack

[XWrench3]

No gas check is for slow, low psi loads with at least semi-soft lead. Gas checks is for higher velocity hard lead bullets. Since you want to run hot rod loads, get the gas checked mold, install the checks, and never look back.

[RobS]

You will end up with one of each...

[smilie=l:

[mroliver77]

I run my .44 mag with upper end loads with plain based boolits. It shoots much better than I can! This gun is set up perfect and is a gem to shoot. I have a gas check mold for shooting softer alloy for hunting. As far as rifle, I dont have .44 mag but a couple 45-70 and shoot without gas check with good accuracy and no leading. I have shot un checked boolits before and some shot well while other designs did not.
Jay

[HeavyMetal]

My issue with gas checks is keeping them on.

Back in the day I sized my 44's to .429 and the gas checks were tight, as I increased diameter the checks were not "tightened" as much and I begin to fear losing one in the barrel.

While fully realizing that with the average pressure of a fired round a gas check staying in the barrel is not likely, I have still moved away from gas checks in all my pistol rounds.

The 429421 Lyman and the RCBS copy, 250-K, are both good suggestions here.

I currently have a single cavity Lyman 44 WFP mold, can't remember the number right now, that has a gas check on it. The mold casts at .433 and boolits weigh about 260.

When money permits this mold will go to Erik at HP molds for removal of the gas check and to get HP'd. I figure to wind up with a boolit with a nice sized base band and weighing about 245 to 250 grains as cast.

I expect it to work very well in my Contender and model 29.

Food for thought on the gas checks.

[Bass Ackward]

If a guy asks a question PB or GC two things come to mind.

1. If he knew how or was confident enough to work with PB, he wouldn't ask this question.
2. No matter which way he goes first, the grass always looks greener and he will turn to the other side.

So my answer to him is always going to be a GC.

[Al_sway]

RobS,
Thanks, I didn't make myself very clear and you did a good job of cleaning things up. Specificly, 308 @ 115/150/180 gr. mouse loads 5 grs powder and under. Mid loads and up would be gas checked.
thanks much
harrya

I often use gas check designs without gas checks for low velocity loads.
Lee 115 grain with 5 grains 700-x, Red Dot, etc. in a .30-30.
Lee 150 grain with 5-6 grains 700-x, Red Dot in a .30-30.
Lee 150 grain with 5-6 grains 700-x, Red Dot in a .308.
All without gas check or fillers, and usually unsized. Nice plinking loads. The Lee 150 load will often do 1.5 inches at 50 yards, and they are rejected casts (my seconds or thirds).

Yesterday I cast a few Lyman 86 grain 6mm bullets for initial sighting in with a .243 Winchester. After casting, I sorted and kept the seconds aside. Used Lee Liquid Alox and loaded them over 5 grain Green Dot without sizing or a gas check or filler. Nice clusters at 25 yards for initial sighting, and then about 2 inches at 50 yards. Nice, quiet and cheap way to get initial sighting in done.

The reason for the vague loads? I use Lee dippers and throw the charges without weighing.

[Lead Fred]

We were using store bought cast plain base boolits 240s at 1400fps.
Pit of an 6 inch Taurus, with no leading.

[MtGun44]

No real need for 'diapers' on your boolits at handgun velocities unless the gun has some
sort of a significant problem with fit, barrel constriction, rough surfaces or other issues.
Added cost, fiddliness and general PITA, IMO.

I regularly shoot to absolute max vel with Keith and LBT designs without GCs with good to
excellent accy and no leading with air cooled wheel wt alloy. Good boolit design, good lube
and PROPER FIT of the boolit are all it takes.

Both .44 Mag and .357 Mag in S&W, Colt, Ruger handguns give the same basic results.
Bill