Paper Patching 308 j-words for the 303 Brit

[303Guy]

I still haven't loaded up any patched j-words. In fact, I haven't loaded up anything (other than a few test loads and fire-lapping loads). I have bought some j-words for loading in one rifle but in testing them for throat fit in a few rifles I found that they are pretty loose. Not too bad for the intended rifle though but even so, they are loose in the neck. This got me to thinking, why not patch them and seat them in unsized necks just like I do for cast patched boolits?

I did something along those lines a few years back and found my notes recently. I had seated the bullets into a paper hand towel 'cup' in the neck and soaked that with molten 'waxy-lube' (some of you might remember). My notes say they were accurate. The powder was Varget (AR2208). I did a test with this same method with a cast boolit and it appears the patch/cup stayed on the boolit through the bore. I noted that the 'cup' stuck to the boolit more than it gripped the neck. Anyway, that was a cat sneeze load. So getting back to patching jacketed's, I have some Speer 180gr RN's that are loose in any chamber that I thought might benefit from paper patching, just to get them align in the throat during launch. Maybe the 150gr Hornady's too although those have a larger diameter to start with. Maybe cig paper? More to think about.

[303Guy]

Well, I patched one with 0.064 mm (.0025") paper and it seats in an unsized neck just fine. It does compress the paper a fair amount. However, the patched bullet does not enter the throat far enough. That's with a .311 180 gr bullet. But, it might just make 123 gr bullets usable in the Brit. With the right powder they can be driven over 3000 fps. All they need is accuracy and the paper patch might just fit in the throat well enough to achieve that. Unfortunately, I don't have any to try (well, I have two or three somewhere).

I've patched a 150 gr (.312) and am waiting for it to dry to check for fit.

[longbow]

I cast up some short 0.301" boolits at 100 grs. (little spire point) from my push out mould, knurled them up a couple thou to suit my 0.303" x 0.314" barrel then patched to a little over groove diameter with high hopes. I figured they could be made to scoot along pretty quickly and be explosive. Well, they went "Bang!" but accuracy was, well... poor to say the least. I figured too long a jump through the throat.

You may have better luck with "J" bullets. Hopefully you do.

You may find the 123 gr. bullets somewhat short though. The 150 gr. should be okay being longer. It'll be interesting to see your results.

I have had good results with my Mihec 316410 boolits at 130 gr. so if the jump isn't too long for those a 130 gr. PP "J" bullet should be okay too.

Looking forward to field test results.

Longbow

[JKH]

I have paper patched .308 jacketed for use in .318 bore 88 commision rifle, worked very well when done right. The best tome on this subject was written by Ross Seyfried, I scanned it to PDF and have provided it before in similar past threads, I would happily email a copy to anyone who wants it, just send me an email to jkhampshireATroadrunnerDOTcom

Jeff

[303Guy]

PM sent, thank you. Things have come to a stand still at the moment. The cold (cool), wet conditions don't help much either.

longbow, the shortest boolits I shot were 147gr. They were particularly short being smooth sided. But they worked well and engaged the throat just fine. They were too short to handle so now my light weights are 168gr. Much more manageable.

I shall await the PDF from Jeff.

[quasi]

I seem to remember Siefried PP 7mm bullets up to .289 dia. for his .275 Rigby, I guess they used .280 Ross specs for that barrel He used Onion Skin paper as I recall and used the rifle for a trip to New
Zealand.

[303Guy]

With the 308 bullet in a 303 bore, I'm thinking that the purpose of the patch is simply to align the bullet in the throat so it enters the bore straight. I'm also thinking that if the patch is going to seal the bore then it needs to seal it consistently from shot to shot. The boolits I have are low drag boat tails which may not be the best choice for testing the principle. Two many variables! Maybe I should load up a few plain bullets and a few patched bullets to see what difference it makes. I have them so all it will cost me is time and powder. I'm thinking I should do it in a larger bore rifle rather than my .303/.313 bore rifle. I do have a candidate that needs a purpose. It has a .305 bore. That does seem to like my 168 gr patched boolit as far as I can tell from captured boolits.

[UBER7MM]

With the 308 bullet in a 303 bore, I'm thinking that the purpose of the patch is simply to align the bullet in the throat so it enters the bore straight. I'm also thinking that if the patch is going to seal the bore then it needs to seal it consistently from shot to shot....

With the 308 bullet in a 303 bore, I'm thinking that the purpose of the patch is simply to align the bullet in the throat so it enters the bore straight.
I agree. In my experience, the patch aligns the bullet. IMHO, the bullet must also be touching the rifling to engage it and fly true.

I'm also thinking that if the patch is going to seal the bore then it needs to seal it consistently from shot to shot.
The patch acts as a plug to seal the the throat. This is critical when loading un-sized fired cases. The patch may end up over "groove size" in order to seal the throat.

[303Guy]

Right, thanks. Alignment, throat filling and sealing, ogive contacting the rifling leade. Makes sense.

Would I be correct that if the above are all met that the fit in the neck is unimportant? Supposing the neck is a little loose on the patched bullet, can I effect a seal and hold with say molten wax? The wax idea being that it will not interfere with patch fragment release on exiting the bore. I can slightly size the necks with a custom neck sizing die. I would prefer not to do that as it could size unevenly although with such a small amount of sizing the runout would be even smaller.

[UBER7MM]

303Guy,

With fired unsized cases, I've found that neck tension is paramount. I like to get my bullets out to the rifling. If I don't have proper tension, the patched boolit falls into the case. Wailing and gnashing of teeth is an unpleasant bi-product. A Dacron polyester filler saves the powder from spilling into the magazine and action when the boolit gets stuck in the lands, and an ejection is necessary.

I'm in the current process of culling my brass for neck tension.


I hope this helps,

[303Guy]

Yes, I always aim for sufficient neck tension to hold the boolit in the magazine. The boolit must not pull out and must not push in. That doesn't take too much.