Can anyone compair results PB vs GC with PC

[cs86]

Wondering if anyone has tested both plain base and gas check base boolits with powder coating. Main thing I'm after is finding out if you can push them about the same speeds before leading or does one find that you can push a GC boolit faster. How about accuracy?

Main reason I'm asking is because there is a group buy for some slick side rifle molds and I haven't seen many shooting PB boolits in a rifle.

[smokesahoy]

I'm ordering one up to try. I actually clicked this forum with the same thing in mind. Getting a plain base no lube groove bullet. There might be a velocity threshold because my recovered 40 shows no deformation of the PC on the base. I was thinking if I reach deformation what about placing a piece of round aluminum foil on the base with a dab of glue and then powder coating? There should be a way of doing this without gas checks and still attaining accuracy at good velocity. Gas checks are antiquated, seems wrong to use them with technology nearly a decade younger.

That's the problem with trailblazing, we don't have tons of experience to draw on

[xacex]

It depends on your expectation of accuracy, and how fast you are going to push your boolit for the given caliber. For plinking, and under say 1400-1600fps a gas check is not necessary. Subsonic shooting in a blackout for instance you will not want a gas check, but go supersonic up into the higher speeds the blackout achieves and you will. There is base deformation at higher pressure that will affect accuracy. Also, it depends on if you are shooting a semi auto. Unless you do not want the action to function for the most part shooting lighter supersonic boolits will require a gas check for acceptable accuracy at the pressure needed to function the action. In the comparisons I have done P/C still deforms, and leads to reduced accuracy in a rifle at supersonic speeds. Pistol shooting is just fine, but the bases are also larger and deform less than smaller rifle boolits do.

[popper]

I tested with RD 30/30 1 1/2 yr ago @ 50 (edit: PB/GC/no GC, all pCd). Didn't have a chrony then but 17 gr 2400 gave equal results. Deleted target pics when I sold the mould. It's going to depend on the boolit design. (edit Evidence was I could not make good enough PB nor was the base band on the mould long enough to take pressure of higher fps load & maintain any accuracy. I'm pushing the 165C to 1650 in the BO (not much room for more Rx7), 1750 in the 308, 2450 w/GC & full case of 335. I have the same boolit w & w/o grooves, someday I'll try to find the limit for both. Think it will go higher, (edit: w/o GC) limit @ 2k?. IIRC someone did ~ 2700 in 223 but no claim to accuracy. Still no leading. No, you won't get near jacketed fps without a GC in rifle. Can you get a decent hunting/range load without GC, Yes.

[ebner glocken]

I used 57 grains of IMR 4350 with a lee 180 (actual weight of 185) for just over 2800 FPS. Accuracy was 6"+ @ 25 yards. Gator checks was used. Sized to .310". No fouling but horrid accuracy. Video is on youtube under my name, I show what was found with an acetone soaked patch.

The other bullet I tried was a 314299 sized the same with a load of 52 grains of IMR 4350 and a velocity of 2300+ fps. Accuracy was once again horrible.

I have now established for my own uses that fouling isn't the issue at these speeds. An accuracy load can surely be found somewhere below this. Would be nice to have both, more testing needed.

Ebner

[hickfu]

If I could get some time to go to the range I could answer that question... I have 2 molds for my 35Rem 1 GC and 1 PB I also have a 35 Cal PB check maker... I want to test this as well but I spend all my days at my kids house to help watch my grandson while they work


Doc

[cs86]

I could probably test this with a regular lube groove mold. Just have to find time myself. I didn't know if anyone has done testing to see the limitations of GC vs non-GC or PB base designs with powder coat. I'm not so much interested into how fast I can push the bullet, but how much more can a GC take then a non-GC or PB base with powder coating. I'd like to try a soft alloy like WW alloy. I'm trying to determine where it makes more sense to buy a mold if you had the option for a GC or PB. I try to avoid GC so it's one less thing to buy and one less step to apply.

[smokesahoy]

Yeah with a plain base it should go better than gc design without GC. Can't wait till my mold gets here and I can test.

[Rushthezeppelin]

I'll be testing this out in 300 BO soon. Got a new NOE mold that drops 2 GC and 2 PB of the same bullet (129gr PT). Should be able to push them I'd think to at least 2200 FPS. Will find out if PBs get worse accuracy or has leading problems at that speed.

[ebner glocken]

If you did your coating right you shall have no issues with leading @ 2200 FPS, even w/o a gas check. Accuracy is the only question left. A load is out there, find it.

Ebner

[Smoke4320]

I have achieved over 1900 FPS with both 6.5 x 55 and 308 GC molds but Pc'ed and NO gas check..98/2 alloy
recovered bullets showed no signs of PC burning off and got very good accuracy ..at 2200 FPS accuracy went to h@@@@ but still got no leading .. have not had time to try linotype alloy to see if I can increase FPS but I think that will do it

[Freightman]

I have all my molds PB .311 but i am not a good tester as I never push very hard. Tried a 200 ge PB PC boolit at max, accuracy sucked, slowed it down to 1800 + or - and accuracy came back.