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Evening all, This forum has helped me out ALOT!!! I'm powder coating, casting and shooting more. My question is about not sizing after powder coating???? Has anyone tried it? Will the excess PC over the bore diameter cause a big rise in chamber pressure, effect accuracy??? Any thoughts..........
Too many variable to give a definitive answer. As long as bullets are only .0015 in excess of the measurement you get when you slug your barrel you should theoretically be fine. However, it would definitely introduce inconsistencies as casting temp of the alloy, alloy composition, mold temp all impact final bullet diameter. Are you powder coating pistol or rifle bullets?
Sizing if you use an upside down lee press does not take much time. You can easily do 1k rounds in under 1.5 hours. If you attach a modified piece of pvc to the press to allow you to feed bullets faster and keep your fingers away from the punch you can size 1k in about an hour. I always size after powder coating. Doesn't take long and gives better consistency.
I shoot for accuracy. Components that vary will not make consistently accurate ammunition. If my ammunition is not accurate then I am wasting my time and my money.
^^^^ What he said. I also hunt, so I want everything to be as close to perfect as can be..
Sizing (or not) totally depends on the slug size of your bore and the dropped size of the slugs you are casting......PC is not a “cure all fix-all” for poor inaccurate casting and loading.
You cannot just assume if you PC a boolit it fits your gun perfectly. I cast and load over 15 different cal’s and some need sizing BEFORE and AFTER PC.....some don’t. All depends on my guns.
PC is not a magic elixer for poor casting/loading techniques!!!!!!!!!!!! It is just a clean & easy replacement for sloppy dirty old grease lubes of the past.
Banger
Unsized bullets are more accurate than sized. Tons of publications on sizing and how it negatively affects accuracy.
As long as the powder coated bullet is of the correct diameter unsized it will be fine.
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Quote:
Originally Posted by Rcmaveric
Can you steer me in that direction? Just curious as I have not seen anything about that published. Thanks in advance.
Slim
Agree!Quote:
Originally Posted by Dragonheart
My goal is to be MOA or under with cast at a 100 yards.
WHHHHHHHHHHHAAAAAAAAAAAAAAAAAAATTTTTTTTTTTTTTTTT?
Proof and links.............PLEASE!!!!!!!!!!!!!!!!!!!!!!!!!!
banger
I was reading an article yeaterday talking about. Cant find it. Go figure.
But ABCs of Reloading on page 100 talks about excessive sizing being bad and then defines excessive sizing as .003 or more.
Then Cast Bullets for Beginners and Experts in few different sections gives both sides of the argument.
I follow the thinking that bigger is better. Biggest bullet that will chamber mean a throat thats filled. A filled throat means a bullet is supported and aligned as well as means no gas cutting from an undersized bullet when the bullet jumps the throat to the lands.
There is also an article on Cast Bullet Association that supports sizing has not effect.
Sorry. I am sailor and fishmen and prone to tall tails. Tons was clearly an over embelshment.
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Will have to go back and read my ABC of reloading, but I don't recall any mention of powdercoating. That was the original question I believe. I actually size before and after, I am that anal on my rifle loads. It has worked extremely well for me, YMMV.
If bullets came out of a mold absolutely concentric then I could see no reason to size. All you would need then would be molds cut that dropped a bullet to the dimensions you desired, but we know bullets do not come out of a mold concentric.
I am going to have to question any publication that tells me the basic laws of physics don't apply and a non-concentric (lopsided) bullet is better choice and it is going to fly straight and not wobble. The wobble may not be apparent at short distances, but as the distance increases and once the wobble starts it is only going to get worse as will the accuracy.
Dragonheart is VERY correct. I worked a number of years in an industry that used some very high speed processes. The raw material had to be centrifugally cast or it would come apart in operation, I’m still carrying a small piece in my shoulder after someone tried to change specification. When center off mass does not match center of rotation very large forces can be generated which can mess up just about anything.
What about the idea the bullet gets sized as it goes down the barrel?
Understand I do size my bullets, some before AND after PC'ing, for sure after PC'ing.
I tried not sizing various rounds in 9, 45acp and 300AAC. There are many members here that dont size their bullets without any issues. There are no accuracy issues as far as I can tell but without sizing you might have problems seating these bullets and you might end up cutting out ring of lead when you seat those. I guess maybe additional expanding of case mouth might help but it wasnt worth it for me. Now I size everything as painful as that may be at times.
I dont think you'll run into any pressure issues because of it. Lead is so soft (even hard lead) that it will get swagged down the barrel without causing pressure spikes.
Best just try and see what you get. I thought I was going to do away with it but ended up going back to sizing after all.
Being conteric doesn’t automatically mean. That center of rotation and center of mass is same—think. Think balancing a tire on you car. With a bullet, it has to be concentric but weight has to be somewhat uniform or it will be out of balance— it takes both to have an accurate bullet.Quote:
Originally Posted by Dragonheart
Quote:
Originally Posted by KenH
I've shot thousandths of unsized boolits before I started powder coating. It depends on the size. Same goes for powder coated as "bangerjim" stated size is what matters.
Boolits go through all sorts of shape changes when fired there's even a term for it (obstruation ?) so I don't fret over it. If a boolit isn't concentric when it enters the bore it surly will be after the barrel swedges it down. I'm talking within reason of course.
Motor
For autoloading pistols, you can shoot unsized so long as you plunk test each round or have a method so that the fat bullet will have zero chance of preventing the round from fully chambering and prevent the slide from closing 100%. If you don't, you are asking for troubles, headaches and lots of failures to fire.
TL round nose design has lots of clearance due to the "step". A 2-3 mil fat bullet will still have lots of clearance to go into the chamber so long as the groove riding portion of the bullet is below the case mouth and the loaded case is skinnier than the chamber of the gun.
The rounds on the right can be seated with the step above the case rim because they were sized so that they fit inside the throat of my 9mm gun. The unsized rounds on the left must be seated with the step at or below the case mouth and the top of the case must not be too fat for the chamber of the gun. You also have to adjust your powder drop for the smaller volume inside the case.
https://images3.imgbox.com/36/3a/LmcvDjiE_o.jpg
Same goes for TC bullets but with a more abrupt taper, you can get away with fat unsized bullets so long as the vertical part is below the case mouth.
https://images3.imgbox.com/22/0a/ZJRso6z9_o.jpg
The rise in pressure from a fatter bullet is negligible. The excess powder coating and causes very little added resistance going down the barrel compared to a sized powder coated bullet.
I use an unsized and PC coated NOE 6.5-125gr to fireform 762x39 brass into 6.5 Grendel and it works great, perfect brass blowout and no leading. Using Smokes powder, one thin coat using the shake method with airsoft BBs. Beats using 30 cent jacketed bullets by a mile. If unsized will chamber easily I try them and am usually surprised by how good they perform, handguns and rifles alike.