if I powder coat LEE C430-310-RF, do I need Gas-check ?

[derek45]

I cast & lubra-sized a bunch of these years ago.

friend of mine just started casting 9mm bullets and powder coating them with Harbor freight red, and another brand light blue.

I stopped by, and we made a fresh handful for me to try.

With a powder coat, and 20gr of H110, from a 5.5" ruger, should I gas-check them or not ?

[Grmps]

your pushing around 1100fps you shouldn't need to gas check them. try a few and see, you can always add checks later

[DougGuy]

Hmm.. Might ought to load one and see if it will seat fully in the cylinder before you load a gob of 'em.. PC makes the boolits bigger and you would want to see if they will slide into the throats from the front of the cylinder. If not, you may have problems loading assembled ammo.

The boolits you are showing in the pic with lube and checks are about as perfect as you could want for that 44, I don't see any advantage from PC'ing for that gun.

[derek45]

I sized and loaded them up, most without GC's

20gr H110

they fit in my Ruger just fine

I'll report how they shoot when I get time

[308Jeff]

Subscribing

[nagantguy]

I pc that exact boolit for revolvers carbines and a contender, I use the check even on less than full house loads cause they shoot much better,my standered load is 18.5 h110 and they shoot better with the Check.

[Moonie]

You don't have to, however they are much more accurate with the check.

[BNE]

Hold on tight. That load will get your attention. I don't use gas checks on mine. The gun and load is still more accurate than me!

[Dragonheart]

To answer your question, no, you do not need a gas check. The powder coating will protect the base of a bullet.

However, a bullet is steered from it's base; Imperfections, slight angle deflection, lack of roundness, etc. are all going to effect your accuracy, especially as range increases. So I guess the question is how important is accuracy to you?

[Lloyd Smale]

never saw a gas checked designed bullet shoot as well without the check. For what they cost use them. IF you want to not use gas checks get a plain based mold.

[P Flados]

I will admit that it is possible that some situations may need a gas check for improved accuracy.

I see this a most likely for rifles (or bolt action handguns) trying to get MOA or less.

For my handguns use I did not find this to be the case. I have 3 gas check molds that have seen plenty of use without checks.

I am currently getting about 4 or 5 MOA from a Lee 150 I am working on for my 10" 30 Herrett. I am hoping to get this down under 3 MOA. I had some good results from my Lee 170 in my 14" 30-30. I previously got to sub 3 MOA from a Lee 200 in my 10" 357 max, see post 65 & 66 of:

http://castboolits.gunloads.com/show...ign-358-200-RF

For my guns (Contender 10" barrels in 30 Herrett & 357 max; Contender 14" barrels in 30 Herrett; 30-30 & 357 max; Dan Wesson 357 Max), I have found that PC coated checkless boolits shoot full power loads just as accurate as any J word load I have been able to work up. They also shoot just as good as my plain based boolits.

My attempts with checks on the 30 cal stuff did not improve anything.

The OP indicated that this was for a open sight 5.5" revolver. For this type of application, there is really just no reason at all that a well filled out checkless boolit from a good mold would not shoot just as good as a plain base or a checked boolit.

[Lloyd Smale]

The OP indicated that this was for a open sight 5.5" revolver. For this type of application, there is really just no reason at all that a well filled out checkless boolit from a good mold would not shoot just as good as a plain base or a checked boolit.

Oh but there is. Its the same reason bevel based bullets aren't choosen for accuracy work. The gasses when your powder ignites don't have a nice clean place to push against the bullet. Which can tend to tip a bullet in the barrel and also has more chance of flame cutting. A gas check gives a perfect base of of a bullet for consistant push and seals this gas blow by. depends on what your looking for. If 3 inch 25 yard groups and rolling beer cans is what you expect out of a handgun then go for it. You can probably accomplish that leaving off checks. But if you wan top velocitys, minimal leading and the best accuracy you can get out of your gun put the check on. If you don't want to use check get yourself a plain based mold. Personaly cant see why anyone would waste money buying a gas checked mold if he didn't intend to use gas checks.

[P Flados]

I am one of those darn anal retentive engineer types that really likes to base my positions on the laws of physics if at all possible. Proof by good honest testing is great too. However, good testing does not invalidate the laws of physics, it just shows us that we need to look for something that was missed.

I believe that the shape of the base is of much less importance than how "true" the surfaces are that allow for the initial escape of gases as the boolit is clearing the end of the barrel. As long as the gas escape path is uniform on opposing sides of the base all the way around, then the base will not be pushed off of the centerline of its path. If I am missing some aspect of a law of physics, let me know.

Note that a perfectly formed "bevel base" boolit is not that much different than a boat tailed J word. On the other hand, lots of bevel base boolit are made in settings where "perfectly formed" is not a priority.

For my boolits, I can get a nice square edge on the boolit where it drops from full diameter down to the shank (the portion intended for a check). If I were to spot any rounding of this edge, I would expect reduced accuracy and would cull it. I also get pretty good square edges at the actual base. I cull boolits if they do not look good at this location.

The non-uniform escape of gases from a plain base boolit that does not have a nice uniform square edge around the base is just as likely to adversely affect accuracy as lack of uniformity in the overall base configuration of a checkless boolit.

Many gas check molds and mold designs exist specifically because this was the only proven way to avoid leading for the intended application. With the reduced need for checks due to the advent of PC, I feel that there are a lot of molds in existence that can provide excellent service when used as checkless. If you also happen to be "value oriented" (as I am) you may also find yourself buying something like a Lee C309-150-F, a C309-170-F, a C312-155-2R or a C358-200-RF with a gas check design just because that is the only way they sell it.

The fact that I have repeatedly gotten the same accuracy from checkless as J words from 3 out of 3 molds with a scoped Contender off of bags (and 3 to 5 MOA is a whole lot better than 3" at 25 yards) tells me that the difference in accuracy potential of a properly formed checkless vs a checked boolit is probably not that big.

If on the other hand you can not get nice uniform square edges on your boolits, I can definitely see where adding a check could improve accuracy.

As far a buying new molds where you have a choice, I would strongly recommend plain base for handguns for anyone willing to use PC. Again, the OP was not about buying a new mold, it was about using one already in hand.

[RogerDat]

At less than $30 per 1,000 checks and being able to put them on as you run the bullet through the sizer makes me ask why wouldn't you apply checks. Sizer costs like $20 from Lee and my most accurate rounds are PC'd and sized. I would say cuts my group size in half from revolver when I do those two steps.

Tip with those big flat noses put them through the Lee sizer base first nose down to install the checks. Checks go on ok base down in a Lee sizer but I think they go on noticeably better base up toward the sizing die so with a flat nose bullet to push against I figure why not.

Easy test, load up a batch both ways, and then have someone else load them behind your back and have them record which loadings are from which box and then mark the targets. You won't know which you are shooting so the results should reflect the bullet absent any bias on your part. I know I can't shoot 8 ball against myself, within a couple of shots I start to "favor" stripes or solids, whichever I'm getting better shots on. My guess is you will see better accuracy on the targets from your gas checked bullets but a real world blind test beats the heck out of any guess.

[Lloyd Smale]

been at this for 45 years and have found in 75 percent of the loads ive worked up for centerfire rifles that flat base bullets outshoot boat tails at a 100 yards. Boat tails may have some advantage way out there but accuracy isn't the advantage. I'm talking hunting bullets here. Most varmint and comp bullets are done as boat tails because there used at extream ranges. truth be told though that its a small advantage even at long range unless your idea of long range is a 1000 yards. Ive probably got 30 different hunting rifles both bolts and #1s and id bet its not but maybe 3 or 4 of them that's most accurate hunting load uses a boat tail bullets.

Note that a perfectly formed "bevel base" boolit is not that much different than a boat tailed J word. On the other hand, lots of bevel base boolit are made in settings where "perfectly formed" is not a priority.

[dryflash3]

I push these pretty hard, I use a gas check.

Every time I've tried a GC, no CG test, the GC always did better accuracy wise.

[WickedColt]

I push these pretty hard, I use a gas check.

Every time I've tried a GC, no CG test, the GC always did better accuracy wise.

Those look great! I'll be PC'ing some soon...like maybe tonight I hope (different cal though).

[DougGuy]

Those look great! I'll be PC'ing some soon...like maybe tonight I hope (different cal though).

See if the sized and finished PC boolits will fit through your cylinder throats from the front. In a perfect world you would want them to slide through the cylinder throats with a light drag fit. If not, then the cylinder itself is sizing them down before they even get to the barrel.

[igolfat8]

I am one of those darn anal retentive engineer types that really likes to base my positions on the laws of physics if at all possible.

I believe that the shape of the base is of much less importance than how "true" the surfaces are that allow for the initial escape of gases as the boolit is clearing the end of the barrel. As long as the gas escape path is uniform on opposing sides of the base all the way around, then the base will not be pushed off of the centerline of its path. If I am missing some aspect of a law of physics, let me know.

Hey P, I am one of those darn anal retentive ME types too. I see one flawed exception to your analogy. Most of my pistols have compensators on the end of the barrels, which directs exiting gasses upward to counteract muzzle rise. These guns are critically accurate out to 50 yards and beyond. I also have non comped guns that shoot just as accurate groups. My coated bullets cut crisp, accurate, round holes with no evidence of tumbling. How would you explain the comps effect based on your statement above?

[Dragonheart]

The fact is a bullet is steered from the base. Imperfections on the base will have more of an effect on bullet path than the nose. A slight angle of the base will alter the path. A lopsided bullet will never be accurate at distance. If the bullet is powder coated then you do not have to have a gas check as the PC is actually a polymer jacket. However, if you have a bullet designed for a GC I would use a GC to achieve the best accuracy.