bullet patching with Teflon tape

[jhalcott]

  Would you need a hard bullet(linotype) or can I get away with a softer alloy when patching with teflon? I'm talking about RIFLE loads in the 21-2700 fps range! Also would you go with 2 wraps as in paper patching or more(4,5,6?) Calibers from 7MM to 35 ,with a heavy interest in .30 caliber.Why would you need another lube (LLA ,FWFL, alox/beeswax)??

[Castaway]

You might want to post this under the Paper Patch forum for more opinions.   Generally, pure lead self-destructs at around 2,200 f/s, so in order to get your wanted velocity a harder bullet would be needed.

[stuffit]

I've watched posts on this subject for several years now and the "fly in the ointment" of teflon patching is that is wreaks havoc with the neck-tension/bullet-pull factor in the loading equation.  Teflon is a super good lubricant and when it completely surrounds the bullet surface in contact with the case neck, there is not much holding back the launch of the bullet when the charge ignites.  Probably with some powders and firearms-caliber combinations, this would make less difference than in others. But this "hang-up" seems to be what has discouraged most interested parties from pursuing this concept extensively.
 
stuffit

[Sir Charles deMoutonBlack]

I use Teflon in my smokeless hunting rifles for small game rounds.  I cast from wheel-weight metal, and wrap them in one turn of "gasfitters" tape (not the thin, 1/2" wide, hardware stuff). 

PTFE THREAD SEAL TAPE MIL SPEC  T - 27730A 3/4" X 520"

I do not size, either before or after wrapping.  My load is Unique, Universal, or Herco, from 8 to 11 grains.  I top the powder with a pinch of teddybear guts, to hold it against the primer.  Velocity is in the 1200fps range.  They usually group at the tip of the lower duplex post in a scope at 4 power.

The advantage for this use is that neither the cast nor the jacketted bullet fouling destroys the grouping of the other round.  The NRA cast bullet project found very early on that jacket fouling and Alox lube fouling were incompatible.  The use of Teflon is neutral in that respect.

I have had very little experience with higher velocity loads.  BTW, I learned about Teflon tape from a Mike Venturino article from about 1976.

[jhalcott]

  After posting this, I decided to do a test. I wrapped some 311466 ,150 gr bullets with 2 wraps of tape.5 were taped then gas checked,5 were gas checked THEN taped. There was no difference in group size and no sign of leading. a 3x scope and sandbags were used The barrel is a S14" contender. The load is 27/IMR3031/wlr. range was 50 yards.
   I wrapped 10 280468 112 gr bullets with 2 wraps and 10 with 4 wraps of teflon tape. Then gas checked them. Loaded into 7tc/u cases on 25/imr3031/cci sr. I shot them thru a 21" and S14" contenders with a 7x scope and used sandbags. BOTH barrels preferred the 2 wrap bullets. The groups were about 2" but the 2 wraps were more clustered with a flier,while the 4 wraps were "patterns" Does that make sense? The alloy is a Lyman #2 mix about 15-16 bhn. NO OTHER LUBE was used and accuracy was not the idea. I plan on using a known accurate load and changing ONLY the llube for tape.I've got to get the chrono fixed to find out what these loads are doing

[jhalcott]

 Stuffit ,it sounds like you were using teflon in revolver bullets. I can see where that would be a problem as the tape would start to unwind at the barrel/cylinder gap.A tighter grip on the bullet MIGHT help,but I don't know what to do about the gap.My 7 tc/u carbine barrel is throated so long I can use bullets 1.125" long in itThey weigh about 170 grains. I used the 112 grain bullets seated the neck shoulder junction. These are only 0.870" long, so they do get a jump start. I had to see the cancer AND blood Dr's today but tommorow I'm going to the range to try to get smaller groups.

[stuffit]

jhalcott,
Actually my post concerned what I'd read reports on, mostly.  I thought I said so but I'm old and sometimes I leave out stuff.     I did try some in my 45 70 after seeing a post that repoted an acceptable degree of accuracy in a .30 caliber cartridge.  I couldn't get them to seat consistantly (ie without shearing the teflon in one way or another  in the process).  I was trying to use it to compensate for some bullets that were not "oversized" enough to shoot well.  They didn't shoot well with the teflon wrap either, and I didn't do any more with the notion then.   I'll be watching and reading and see if you can learn something good about this taping thing that I can put to good use.  I didn't mean to sound like a "naysayer".  Definitely in your cheering section.
 
stuffit