need more schooling

[panhandle]

OK after earlier discussions I slugged my barrels on the win 94's and they came out .309" while my old O3A3 was .308". so I polished my LEE sizer die out- a little too much naturally, throwing them right at .310" . I figured a little over is better than under and I had to use several coats of Hitec on the 173 grain flat nose I'm casting from a LEE mold to consistently get that. all seemed well and I have experimented with copper gas checks and some aluminum ones a friend has been making. I had mixed results with dirty bore on the winchesters after 10 rounds or so and quickly get into hard chambering after 7 or 8 rounds of about 10 grains of unique. my old O3A3 with it's nearly new 2 groove barrel shoots a 14 grain unique load very nicely but as the others after 8 to 10 rounds chambering becomes very hard.I measured the OD of the neck with the .310 bullet diameter in them and they are running right at .338" . my old Lyman manual doesn't give me that maximum diameter. the first few though, chamber and shoot fine. I have neck trimmed to .010 below max case length and the O6 rounds are going 3.230" length loaded which is which is well under the max loaded length in order to get the first 2 driving bands into the case. They feed nicely from the magazine and show no signs of interference on the lands. I'm satisfied with the grouping with the stock sights on the O3 but I kinda wanted to shoot a 50 round match with it just for fun and that ain't gonna happen at this rate. I'm not using lube other than the Hitec coating.I recovered one from the dirt bank after shooting at 80 plus yards and it mushroomed very well and the copper gas check stayed on and what base still showing looked very clean as far as engraving. it would make a fine 100 yard hunting load I'm sure.but I want to punch paper for fun

[Dusty Bannister]

Is it possible that you are getting too much of the Hitech material on the nose of the bullet, which transfers onto the barrel throat?

[popper]

Sounds like the hitek is not cured completely. I did 2 coats, first very thin, second to get color. Gold 1035. Difficult to get cured without turning brown. I WD to get harness and they turn brown after 1/2 hr cooking. I gave up and went to PC as it almost always works. 310 should be fine, you are about 1500 fps. If neck of fired case has lead, pressure is not high enough and chamber gets a ring of lead.

[megasupermagnum]

I also think your coating is causing the problem. Powder fouling shouldn't cause much issue, especially not that quickly. I've never seen a 30 caliber rifle that wouldn't take a .311" bullet with room to spare (obviously purpose built target rifles are an exception), and you are sizing .310". I'm sure your problem is either in the throat, or your bullet nose's are too tight. I don't know much about coating, but from what I understand Hitek is a very thin coating. If you are adding more than .001" to your bullet, I think you are using too much. It seems to me that there is a much longer learning curve to Hitek than any other thing out there. It's good because it is thin, it doesn't alter the bullet too much. In your case, you might want to try regular powder coat, as it sounds like you want to add some diameter.

An easy test you can do is just lube some bullets. Either wax lube or Alox tumble lube would be fine. If you can shoot 20-30 of those with no issues, you know your issue is the coating. There are a bunch of threads on how to perfectly apply Hitek on this forum you can find.

[panhandle]

OK that makes a lot of sense. I will cast another batch and skip the coat,lube with ALOX and see how it does. they seem to come out undersize without the coating using pretty much wheelweights but the springfields with their 308 bore should be fine. the winchesters being 309 might be a little iffy. but maybe the coating is not the answer. I do 3 to 4 coats for buildup using a 400 degree 10 minute cook with cool down and re-coat between. they pass the acetone wipe test and smash test fine but still could be a problem worth checking

[Mk42gunner]

Or you could get a mold that drops large enough to size down without trying to coat it bigger. Maybe beagle your existing mold.

I bought the Lee 312-185 years ago and it works well sized to 0.311" for my single shot .30-30 and the military chambers in my .308 and .30-06 bolt actions.

Robert

[Thumbcocker]

FWIW I size all .30-30 and .30-06 to .311.

[dondiego]

OK after earlier discussions I slugged my barrels on the win 94's and they came out .309" while my old O3A3 was .308". so I polished my LEE sizer die out- a little too much naturally, throwing them right at .310" . I figured a little over is better than under and I had to use several coats of Hitec on the 173 grain flat nose I'm casting from a LEE mold to consistently get that. all seemed well and I have experimented with copper gas checks and some aluminum ones a friend has been making. I had mixed results with dirty bore on the winchesters after 10 rounds or so and quickly get into hard chambering after 7 or 8 rounds of about 10 grains of unique. my old O3A3 with it's nearly new 2 groove barrel shoots a 14 grain unique load very nicely but as the others after 8 to 10 rounds chambering becomes very hard.I measured the OD of the neck with the .310 bullet diameter in them and they are running right at .338" . my old Lyman manual doesn't give me that maximum diameter. the first few though, chamber and shoot fine. I have neck trimmed to .010 below max case length and the O6 rounds are going 3.230" length loaded which is which is well under the max loaded length in order to get the first 2 driving bands into the case. They feed nicely from the magazine and show no signs of interference on the lands. I'm satisfied with the grouping with the stock sights on the O3 but I kinda wanted to shoot a 50 round match with it just for fun and that ain't gonna happen at this rate. I'm not using lube other than the Hitec coating.I recovered one from the dirt bank after shooting at 80 plus yards and it mushroomed very well and the copper gas check stayed on and what base still showing looked very clean as far as engraving. it would make a fine 100 yard hunting load I'm sure.but I want to punch paper for fun

Have you tried a really dilute coating of LEE liquid alox right out the mold? Try that!