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barrabruce
01-28-2020, 06:30 AM
One for the brains trust

I have some 0.310" pp’ed bullets that if I breachseat firmly enough they will about 60 thou ahead of the chambers neck .
Nicely seated in the tapered lead , engraved and capsulated.

But that is 200 thou ahead of the case mouth.

Leaving 200 thou of case neck outside diameter free bore.

How does one use 15-16 grains of powder in a 30 wcf . For a full load of fast powder.

If I use a filler like Dacron and a cardboard or even paper disk on the case mouth they will be still a couple of hundred thou short.

I know shutzen shooters do it with soft plain base lead bullets but they would have less pressure than
a 1700 -1800 fps load.

I am thinking of chamber ringing from the effect of filler not being on the bullet base.

Any thoughts.

I don’t think I could get away with just the powder in the case un restrained.

A 200 thou scrunched up piece of grease proof paper behind the bullet before the case maybe.
Or a wax wad somehow inserted?

I was playing around cos it was raining and I have a few hundred rounds of powder left in an old tin to use up.
And now one batch of patched bullets lube from the extreme heat has softened.
Making the outside wrap of patch to allow compression by a simple push tool.

Any thoughts experiences welcome.

They could just shoot fearsomely awesome.
Or not at all.
Cheers.

I really don’t want to ring the chamber.

Dan Cash
01-28-2020, 04:25 PM
Bruce, I really don't think you would damage the chamber if you load with something like a dacron fiber plug to retain the propellant as long as you are not using black powder. I do believe trouble would follow if you used something over powder which would form a piston but not be in contact with the bullet base as it would be analogous to an obstructed bore. Wads or fillers on top of smokless powder makes me very uncomfortable.

Gtek
02-01-2020, 09:37 AM
I was a pea of Kapok user but only over 14 of 4227. Some of the 32 Miller crowd was using Floral foam cut into thin sheet and pushed down over case mouth with thumb to install.

barrabruce
02-01-2020, 08:00 PM
Thank you gentleman.
I may stick to a pea size Dacron.
I have fired thousands of loads using that technique no noticeable side effects but not in this application.

Others say it is the most sure way to ring a chamber.

Dan Cash
02-02-2020, 02:49 PM
Let us know how it works. You are an adventurous fellow.

Jniedbalski
02-03-2020, 09:14 AM
I would also like to know. Got a 308 win I would like to try this in

centershot
02-03-2020, 11:54 AM
Bruce, I really don't think you would damage the chamber if you load with something like a dacron fiber plug to retain the propellant as long as you are not using black powder. I do believe trouble would follow if you used something over powder which would form a piston but not be in contact with the bullet base as it would be analogous to an obstructed bore. Wads or fillers on top of smokless powder makes me very uncomfortable.

Years ago, I ruined a really nice Winchester XTR doing exactly that! Don't do it!

barrabruce
02-04-2020, 11:32 PM
Taking all things in to consideration.

I think I’ll gut out of it.

I will try a cutting grease wad with the seater and placing it between the base of the bullet and case mouth thou. In the longer seating arrangement.

And

With seated with the base next to the case mouth using conventional methods of powder positioning.

Maybe I should just use a kicker charge of fast powder over a case full of real slow powder with a card wad on the mouth of the case.

Anyone ever tried dried used coffee grounds?

I could keep making up a handy supply.

How the mind wanders when you have an infected toe and there is nothing on the oogle box you can bring yourself to watch.

303Guy
02-05-2020, 11:36 PM
Have you considered Trail Boss?

barrabruce
02-06-2020, 09:16 AM
No I haven’t considered trail boss .

I don’t want to buy a whole heap to try either.

Maybe if I could get a small amount to try I would.

Seems or seemed to be the flavour of the month a few years ago.
The people I know who have used it didn’t seem to get any great shakes in accuracy out of it.
Then again they said things like.
"It’s a slow powder"
"If you compress it you can get 2000 fps out of it"

Ha not for me thanks

303Guy
02-06-2020, 04:15 PM
It's marginally slower than AS30N but a lot bulkier which makes powder position a non issue. More expensive too I think.

I did once try a breach seated boolit. I had a case with a damaged neck or something so I cut it back to behind the shoulder. I must have used a tuft of dacron to keep the powder in place. It fired Ok with no signs of abnormal pressure (it was a low pressure load) but - there was this big inward collapse at the case end! No gas leakage. I think I would want the base of the breach seated boolit within the case neck which wouldn't be a problem with an unsized neck given a slight flare.

Oh yes, there is a specific warning not to compress Trail Boss as dangerous pressure could result.

Dan Cash
02-07-2020, 11:07 AM
303 Guy, The collapsed case neck is a symptom of insufficient pressure with a slow powder. Even a relatively fast powder like Reloader 7 in insufficient quantity will cause neck collapse and sooty cases.

Gobeyond
05-06-2020, 11:39 PM
If you had a 6.5 to shoot that far into the rifling, it might do it with their longer bullets. Try a lighter longer bullet to shoot in that lever gun, and hook up a little into the case. Zinc or copper, single shot.
Or extend a PP to the case from a .300 bullet.