Paper patch/breech seated loading

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J.Murphy
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Paper patch/breech seated loading

Post by J.Murphy »

This is new for me as a high power and grease lubed silhouette shooter. When loading for paper patch or breech seated where the powder basically fills the entire case, how do you measure the powder and then compress what would normally overflow the case? Can drop tube filling a full case, a wad and compress compare to weighing each charge? How do you end up with a flush case mouth of compressed powder for breech seating? How does volume metering compare to weighing each charge?
John Murphy
martinibelgian
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Re: Paper patch/breech seated loading

Post by martinibelgian »

For me, the answer is simple - don't compress. At least, not a lot. Since I'm shooting Swiss, compression isn't required. And since I'm shooting BN cases, not a good idea either. If one absolutely had to compress, I suppose it could be done in stages, but I really don't see a need for it. even in a 45-70 case, you'll be getting 80+ grains of powder in, so no problems of not getting enough powder in there...
For me, compression is a result from adding powder or seating the bullet deeper, not a requirement. And you don't need the case mouth flush with powder, no need. Even when breech seating.
gunlaker
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Re: Paper patch/breech seated loading

Post by gunlaker »

For breech seating I weight a charge that fills the case when drop tubed. Then I drop tube the case full and then add a 0.030" veg wad. Next I compress maybe 0.060" with my press.

When breech seating the bullet, I sometimes use an additional 0.030" or 0.060" LDPE wad in the seater tool under the bullet.

Chris.
Woody
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Re: Paper patch/breech seated loading

Post by Woody »

I have found that a case full of uncompressed powder will cause case stretching and premature case failure. Compression of the powder slows or stops this. You can compress the powder into the case by using a tube funnel that allows you to overfill the case and with the funnel still in place, allows a compression die to compress the overfill into the case. They are simple to make and slip over the outside of the case instead of entering the case as in a regular funnel.

Using this method, I have completely breech seated the bullet and then load the charged case separately. Makes for some interesting recoil in a 45-90 pushing a 550 grain bullet.

Woody
Richard A. Wood
If you are surrounded. You are in a target rich environment.
BFD
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Re: Paper patch/breech seated loading

Post by BFD »

Gert, I think the rules are changing with respect to Swiss and compression.
semtav
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Re: Paper patch/breech seated loading

Post by semtav »

Im about to find out how much it will tolerate.
My most accurate GG load was my 40-82 with 80 gr Swiss 1.5 compressed .3 in
To get my PP bullet where i like it, im going to have to compress it .45 in
Tried one and its doable;.
bruce m
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Re: Paper patch/breech seated loading

Post by bruce m »

be careful compressing droptubed charges of swiss a lot.
there comes a stage where cases bulge and are hard (tight) to chamber.
bruce.
ventum est amicus meus
bruce m
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Re: Paper patch/breech seated loading

Post by bruce m »

I have done a fair bit of breech seating bore diameter pp bullets in 40/72 using 405 win brass, and 45 x 2.4" using starline.
I droptube the powder such that about 0.030" of a 0.060" wad is above the case and compress so that the wad is even with the top of the case.
tuning is done by adjusting the gap between the base of the bullet and the wad until tightest grouping happens.
when this happens, accuracy can be scary good.
40 and 45 cal prefer a bigger gap than 38 cal, and 32 cal a little less again.
1/8" is about the mark for 40 and 45 cal, and 1/16" for 38 cal.
I have never had cases lengthen.
some guys are leery of the airgap, but this is how it was done in the day with soft barrels, and I have never bulged a barrel, and it still works now.
patched bullets are ideally a little firm in the bore so that they are firm to seat, and will not move until the big red flame happens.
it is funny to look up a bore with a breech seated bullet in it, as you can see light around the bullet.
bruce.
ventum est amicus meus
semtav
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Re: Paper patch/breech seated loading

Post by semtav »

bruce m wrote: Thu Nov 28, 2019 4:11 am be careful compressing droptubed charges of swiss a lot.
there comes a stage where cases bulge and are hard (tight) to chamber.
bruce.
Thats what I was worried about. But the one i tried chambered ok so we will see what happens when i do 15 of them.
Gonna try to compare that to ones compressed .030 if i can cam them in the chamber that far.
Im camming the .45 ones in over an 1/8 of an inch.

How do you keep from spiilling powder when you do it that way Bruce? ( After they are done and in the ammo box)
SSShooter
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Re: Paper patch/breech seated loading

Post by SSShooter »

BFD wrote: Wed Nov 27, 2019 7:02 pm Gert, I think the rules are changing with respect to Swiss and compression.
Brent - don't leave us hanging. How about an explanation? How are the rules changing?
Glenn
BFD
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Re: Paper patch/breech seated loading

Post by BFD »

The old rule was Swiss does not need compression. That was never 100% true, but it did underscore that very accurate loads could usually be found that used very little or no compression. Those powders were relatively dense.

Today's powder lots are pretty uniformly less dense than powder lots beginning in 2013. The more recent of these (2016-2018) seem to require at least moderate compression to achieve similar or near similar levels of accuracy.

Remember rules are made to be broken and there are always exceptions.
Woody
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Re: Paper patch/breech seated loading

Post by Woody »

I agree with Brent. Seems like the current lots of Swiss, (2017 and 2018), respond better to more compression than I used to apply.

Woody
Richard A. Wood
If you are surrounded. You are in a target rich environment.
bruce m
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Re: Paper patch/breech seated loading

Post by bruce m »

semtav,
my wads have a slight friction fit which is fine for general handling as when shooting.
for travelling I put something in the ammo box so when the lid is closed it holds the wads in even if you drop the box.
you could lightly squeeze the case neck on the wad with s crimp die if you wanted, but not enough to cause it not to sit flat.
are you breech seating bore or groove diameter bullets?
incidentally, my 45/2.4" loads take just on 100 gns powder.
bruce.
ventum est amicus meus
semtav
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Re: Paper patch/breech seated loading

Post by semtav »

Bruce ,
Im shooting groove dia PP bullets, but I'm compressing the load and seating the bullet. My 40-82 just happened to be as you described with 80 gr powder before compressing it. Im camming the bullet into the rifling 1/8 in or more.
Brian
semtav
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Re: Paper patch/breech seated loading

Post by semtav »

Bruce my initial reply was in response to Brett's comment on Swiss compression, Not breach seating. Ive always compressed Swiss a lot.
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