Where do I go from here? PC and no "workee"

RicinYakima

High Steppes of Eastern Washington
Ok guys, here is what happened today. Took a 1932 Springfield National Match rifle out of the safe to shoot. Found some empty brass and loaded ammo. 15 rounds of my normal match load (Lyman 311284, sized .311" with Grey #24, seated to firm seating) and eleven rounds of left over PC bullets from an article I wrote for the Fouling Shot 3 years ago. After shooting 5 foulers, I shot ten rounds of traditional and then 1 fouler and ten rounds of powder coated. These were sized in the same die at .311" and the nose tapered in the same die as the traditional bullets.
First the traditional:
traditional '284.JPG

Now the powder coated bullets.
powder coated.JPG

Why am I not getting groups like others on the internet are saying they get?
 

fiver

Well-Known Member
IMO it's cause your not treating them like something different.
try bumping the load up about 4-5%.
 

Ian

Notorious member
Are you going to write another article?

Actually, lot more happened inside that rifle than you described, and where you go from here is entirely up to you. In case you didn't realize it, everything you need to understand in order to get easy 1.5 MOA or better .30-caliber groups from 950 to nearly 2400 fps has been explained and demonstrated right here on this board. Do a little reading and then you'll start to realize some things you did differently that are not working very well. If you do not understand why those things didn't work, ask questions.

Two home cooks can take the same cake recipe and produce two completely different results, see my signature line.
 

RicinYakima

High Steppes of Eastern Washington
First, I read 95+% of every post on this web site.

Fiver, Is .64 grains going to reduce the group size by 200%?

Ian, OK Bullets of same alloy, same sizing die, loaded same day, same powder charge, same primer and 500% larger group? What needs to be different? I only have 35 match grade PC bullets left from the experiment. The guy that did it did very good work, less than 2% variance, evenly coated and look perfect.

Ric
 

fiver

Well-Known Member
you've changed the friction variable of the bullets by adding the coating.

remember when moly coating was the new big thing?
but nobody could get them to shoot for a while, and then someone broke out a chronograph/pressure trace and really studied things.
they discovered that they needed to bump the powder amount to bring the velocities back in line with the non coated bullets.
this is the same thing happening.

I'm not saying going up .6grs. is going to magically shrink your groups 500% but if I were going to pursue using coated bullets that would be the first step I'd take.
I would also drop the load .6grs. and see what I got.
just putting a coating on the bullet and shooting them next to a non coated bullet only proves that the coating changes things.

not knowing the velocity/twist yadda-yadda all I see is that the holes are further apart and that many of them are oval shape, this indicates to me more speed is needed.
 

RicinYakima

High Steppes of Eastern Washington
Thanks fiver. I have 35 bullets left to experiment with and haven't clean the bore. So will load ten with 5% more and ten with 10% more. Holes look funny because the target backer is cardboard and is warped, so target is stapled up wrinkled.
 

Eutectic

Active Member
Are both targets stapled on the same backboard spot Ric? The conventional bullets look to be a cleaner hole. PC holes sure look to have 'yaw' going on. What velocity? I'd move like fiver said a little faster..... and see.

Pete
 

Ian

Notorious member
Ric, suppose you are an accomplished water-color artist who does illustrations for books and the like. One day you meet someone at the art supply store who's raving about acrylic paints, so you decide to buy a color set and try them. You use the camel-hair brushes and all the techniques you know that work with water-colors, but it makes a mess and the paint is clumpy, streaky, doesn't blend well, etc. because you are applying very good but wrong tools and techniques to the medium. That's essentially what you've done here, because adding the coating CHANGES EVERYTHING.

This stuff is all about dynamics, whether jacketed, paper-patched, coated, or bare/lubricated. Each type requires its own techniques to get good results. Dynamic fit and powder burn rate are changed dramatically when you put a slippery, tough coating on a cast bullet, and this can hurt you or help you depending on what you do at the casting and loading benches. I can tell you to pretty much do the opposite of what you'd do for a CBA match load and it will work better with PC'd cast because PC'd cast doesn't like a jam fit (often they benefit from jump and wiggle room), doesn't generally like a brittle alloy, doesn't like exactly matching tapers, doesn't like to be sized much larger than groove dimension, needs consistent and firm neck tension, and accuracy doesn't tolerate position-sensitive powders or ignition variances very well. This is why I wanted you to (re?)examine some of the threads here that contain successful pc loads and determine what you are doing differently from those, since you have the rifle and made the ammunition for it and know what you did, and none of the rest of us do.

Here's an example:
20180912_214613.jpg
If my chicken scratching doesn't show up well, the basic info is .308 in WCC 08 brass, SA M1A w/22" pencil barrel, suppressed, left group at 75 yards, next five rounds from the magazine are the right group at 100, 37.0 grains of IMR 3031, Lee C312-155 (Ed's grease-groove design), powder coated, gas checked, lubed with LBT soft, sized an actual final of .310", 10.4 bhn 50/50 COWW/purish scrap, air-cooled, aged at least a year, CCI 200 primers, seated to crimp in the crimp groove (which is a lot of jump, IDK how much but probably over 1/8").

Now, what did you differently? My guess is your coated bullets are cast of linotype, parked tight in the throat, and launched with fast powder like Titegroup. Whatever it is, compare to how you did it to how I did it and let's talk about the differences and why they matter.
 
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JSH

Active Member
Lol, this brings to mind the old cigarette ad on the back of a lot of magazines when smoking was in "some would rather fight than switch" and the man or woman, both were used, would have a black eye.

Well gents, I will have two black eyes and couple of missing teeth. I tinkered with PC enough that I decided I had way to much time,energy and effort in my antique or vintage type CB's.

I will sit and lube as I read on the powder coating.
Jeff
 

RicinYakima

High Steppes of Eastern Washington
Are both targets stapled on the same backboard spot Ric? The conventional bullets look to be a cleaner hole. PC holes sure look to have 'yaw' going on. What velocity? I'd move like fiver said a little faster..... and see.

Pete
BAcker is 3 feet wide, the traditional load was on a convex face, but the PC load was shot with a concave wrinkle about at the X ring.
 

RicinYakima

High Steppes of Eastern Washington
Ric, suppose you are an accomplished water-color artist who does illustrations for books and the like. One day you meet someone at the art supply store who's raving about acrylic paints, so you decide to buy a color set and try them. You use the camel-hair brushes and all the techniques you know that work with water-colors, but it makes a mess and the paint is clumpy, streaky, doesn't blend well, etc. because you are applying very good but wrong tools and techniques to the medium. That's essentially what you've done here, because adding the coating CHANGES EVERYTHING. OK, I will go back and look some more.

This stuff is all about dynamics, whether jacketed, paper-patched, coated, or bare/lubricated. Each type requires its own techniques to get good results. Dynamic fit and powder burn rate are changed dramatically when you put a slippery, tough coating on a cast bullet, and this can hurt you or help you depending on what you do at the casting and loading benches. I can tell you to pretty much do the opposite of what you'd do for a CBA match load and it will work better with PC'd cast because PC'd cast doesn't like a jam fit

Yep, 0.005" jam on the tapered front band into the lead.

(often they benefit from jump and wiggle room), doesn't generally like a brittle alloy,

Alloy is about 3.5% antimony and 2.2% tin from my lot of alloy that does BHn 14.

doesn't like exactly matching tapers, doesn't like to be sized much larger than groove dimension, needs consistent and firm neck tension,

Consistent 0.001" interference fit, no crimp.

and accuracy doesn't tolerate position-sensitive powders or ignition variances very well.

This lot of Alliant is not position senitice at 1425 f/s and SD of 15.

This is why I wanted you to (re?)examine some of the threads here that contain successful pc loads and determine what you are doing differently from those, since you have the rifle and made the ammunition for it and know what you did, and none of the rest of us do.

Here's an example:
View attachment 6804
If my chicken scratching doesn't show up well, the basic info is .308 in WCC 08 brass, SA M1A w/22" pencil barrel, suppressed, left group at 75 yards, next five rounds from the magazine are the right group at 100, 37.0 grains of IMR 3031, Lee C312-155 (Ed's grease-groove design), powder coated, gas checked, lubed with LBT soft, sized an actual final of .310", 10.4 bhn 50/50 COWW/purish scrap, air-cooled, aged at least a year, CCI 200 primers, seated to crimp in the crimp groove (which is a lot of jump, IDK how much but probably over 1/8").

I need to stay above 1150 f/s at 200 yards, so light bullets are not in the picture. Even Military Class I need 1 1/4 MOA at 200 yards.

Now, what did you differently? My guess is your coated bullets are cast of linotype, parked tight in the throat, and launched with fast powder like Titegroup. Whatever it is, compare to how you did it to how I did it and let's talk about the differences and why they matter.


So, I need more speed, longer jump, slower powder softer alloy?
 

fiver

Well-Known Member
I think you see the point.
basically the difference is like black powder and smokeless powder paper patching.
your still following the basic tenants of wrapping and paper choices, but then things start diverging as far as core diameters and bullet choices.
it's another skill set to learn.
 

Ian

Notorious member
Oops, I didn't see that at all on my phone, but it shows up great on the 'puter.

I think your alloy is fine, similar (with less tin) has been working great for me. So has a much weaker alloy.

Bullet fit may be a problem. If the contact area of moving tapers collide all at once, the bullet cone tends to get made to throat shape (and direction!) right then, regardless of what the back end of the bullet is doing, like trying to wiggle out of the case and funnel into the throat entrance. If you start a tapered bullet against resistance, the base tends to rivet or get shoved sideways to the limit of the chamber neck clearance and scrapes on through, smearing the bands on one side as it goes.

OK, so here's the whole deal about dynamic fit in a nutshell, and is lost on most everyone: What works best for me, coated or otherwise, is a combination of bullet nose and throat shape that allows for two things......gradual increase in engraving resistance from none or very little at rest to peak force required to squirt the bullet into the bore, and some wiggle room between bullet and throat as it is moving so it can self-align dead center in the throat without any part of the bullet bending or deforming during the critical first few tens of thousandths of an inch of movement. That's it. If you can get your bullet to do that, you got it made and a lot of the other things that people fuss over to get MOA or a little better become irrelevant. Achieving this kind of dynamic fit happens by first selecting a combination of bullet profile and throat to self-align gradually on strong surfaces (NOT the tops of the lands), but to pull the dynamic part off the alloy has to be just right and the bullet has to be presented to the throat with just the right amount of powder pressure at the right time, and that pressure needs to increase by the right amount at the right time until the gas check is all the way into the rifling. Powder coating makes everything in this paragraph a lot easier to achieve because the skin is tough enough and slick enough to allow the bullet to funnel well with little damage even with a soft alloy underneath, therefore alloy and powder is a lot less critical although there are still limits and happy zones. Powder coating also reduces the tendency of the drive side of the land engraves to wear away and leak gas, so higher accurate velocity can be achieved with softer alloy and less attention to detail. The coating also makes bullet lube unnecessary in many instances and eliminates the inconsistencies that lube can introduce.

I think you need to sizer your bullets to .310" and increase your neck tension to a full .002" interference fit. Seat so the bullets have about .020" run at the throat. It still may not work well because of the matching tapers, but I bet you'll see an improvement. If you have a 2° nose-bump die you might try reducing the bullet nose taper with that a little, at least a little way up the nose at the point where it's contacting the throat. If your elbows and retinas can take it, you could also consider pushing those bullets to around 22-2400 fps with a medium rifle powder.

If you want to try that and see enough improvement to warrant further effort, send me a pound cast of that rifle and I'll see if I can fix you up with some better-fitting bullets.
 

Eutectic

Active Member
Question on PC vs. conventional lube......... Is there a repeatable pattern or result that shows up if this is the only thing changed in our load?

Pete
 

RicinYakima

High Steppes of Eastern Washington
Pete,, Just my poor shooting! Shooting with issue '03 sights with that .060" aperture two inches ahead of the action increases my sighting errors. On the traditional target one bullet would be in the cluster and next would be an outlier. With the PC they were random strikes.
 

RicinYakima

High Steppes of Eastern Washington
Ian, Thank you for the reply. That is a lot for me to chew on, as some is against everything I have learned about reloading. However, I will take your advice and work on this for awhile this fall. Thank you for your advice. Ric
 

JWFilips

Well-Known Member
Ric Did you resize the bullets after coating them?
Also did you recheck your C.O.L. with the PC'd bullets
 
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popper

Well-Known Member
I don't see where you said what the alloy is, WD, HT,AC? Secondly I'd advise to NOT crimp, just remove the bell. I've done good with LG PCd but changed to no groove PC. Lube in the groove provides more 'strength' to the alloy as it is moving. You also didn't indicate if you pushed a patch down the bore before the PC shots. I used H335 with the LG 31-165 but changed to H4895 for the no groove mould. Tad over MOA @ ~ 50 yds (32F prone, not fun) with the 335. Better casting, grooveless mould and much better shooting = MOA @ 200. Basically learned a lot in 2 years. And IIRC, added Cu to the mix.