.45 Cowboy Special blow back

[Bunk Stagnerg]

In regards to .45 Colt blow back for some reason I have very little blowback using .45 Cowboy Special cases rather than the full size .45 colt case with a Big Lube™ 210 grain bullet and 1.3 c/c FFFg gun powder in my 1860 Henry and in my revolvers, which are a pair of USFA .45 Colts to mitigate recoil somewhat I use a 170 grain Slim™ and the same 1.3 c/c FFg powder.

Both loads compress the powder slightly and shoot nicely with very little blowback even with such a short case. There is some staining on the lifter block but at our last month match I shot 6 stages (60 rounds) through the rifle without cleaning and it never hesitated or slowed down. In part my suspicion is the positive slam down modification to the lifter arm (thanks Coffinmaker), but the stains on the cases did not go all the way back to the case rim in any gun.

The rifle stays cleaner with the .45 Special (.45 short) than with full size cases and a 2.7 c/c compressed load of FFFg and the 210 grain bullet. Perhaps a heavier bullet might make a difference, but I use what I got. At least that is my observation.

If any one has an observation I would like to hear it.

Yr’ Obt’ Svt’
Bunk

[wildman1]

Couple things come to mind. Cases might be newer (softer), dies might not be sizing them quite as small. As far as blowby into the action or receiver the case rims are larger and should stop some of the passage of gases. wM1

[Dick Dastardly]

Since I've been using the same load and brass, I'll chime in here.  It seems that the wall thickness of the C45Spl. brass is thinner and thus expands to fill the chambers better than 45 Colt brass does.  1.3cc FFFg is the correct load for that bullet in that brass.  It shoots sweet and accurate with minimum recoil.

DD-MDA

[Advertising]

[Noz]

I have conversion cylinders for a pair of 1860s that are no longer usable as cap and ball.  I size my C45S cases in 45 ACP dies and I get a huge amount of blowback. Enough that I have set them aside and they are designated as "use only when rain water is up to my knees".

[Coffinmaker]

OK OK OK OK ....... MY TURN ... MY TURN ....... DDD is correct as confirmed by his pal Smedley.  The wall thickness and neck thickness of the C45S case is a smudge thinner than the usual 45 Colt.  The result is better obturation (expansion) of the case and case mouth in the chamber for a better gas seal.  Less Blow-By.  A good thing.

Now let us address some common miss-conceptions.  #1.  You can resize with 45 ACP dies.  No you can't.  Well, you can, but you shoot yourself in the foot by doing so.  As NOZ has found out the hard way.  45 ACP neck diameter is .473 and the base is .476  You should note, that is a tapered case.  Not actually straight walled.  So you have sized the C45S case to a taper.  Not a good plan, because .......
The 45 Colt case is bigger.  A lot bigger.  Neck is .480 and the base is .480.  Let us extrapolate.  You may have an oversize chamber (most likely with a rifle) and a .480 Case won't expand to seal it.  So, you take a C45S case a size it even smaller.  No way it can seal.  You get massive amounts of blow-by.
Normally, I try not to be too contrary (if your believe that ......) but contrary to some miss-guided golden information, you CANNOT SUCCESSFULLY load/reload C45S with a set of 45 ACP dies.  So put that cost saving idea smooth out of your mind, unless your dead set on ruining all your C45S cases.  Roll crimp.  Roll crimp FIRMLY.

Some suggestions.  45s generate Blow-by.  PERIOD.  It can be mitigated.  Eliminated??  Probably not.  The problem is really bigger in rifles than in revolvers.  With the C45S cases actually being a mite thinner (no, I don't know how much) and perhaps a mite softer, they do obturate better and you get less blow-by.  Further ....... Neck Size only.  Neck size to the depth of the given bullet you are using and leave the rest of the case alone.  Your results with revolvers will be really good.  Rifles???  I take no responsibility at all.  Rifles have chambers all over the place.  Almost NONE of which are at the tight end of SAMMI.

Coffinmaker

[Bunk Stagnerg]

.45 Special (short) is what I mostly shoot using the DD prescription of powder and bullet.
Since I de-cap cases before I wash and clean them I just run the case about half way in a sizing die just to round up any bent case mouths but not far enough to full length size them.
The sizing die is Lee carbide .45 Colt die. The seating and crimp dies are some that came out of the extra stuff box. This whole mishmash is in my Dillon 550B.
I prime and neck expand on the Dillon, charge the cases one at a time with my “black dipper” then use the Dillon to seat and crimp. It may not be the most efficient set up, but it works and no matter what anyone says I do not want a pipe bomb with ½ pound of FFFg right in front of my face. I ain’t no beauty but I would rather have people say “he looks so life like” rather than “Kriminetly! where is his head”?
Yr’ Obt’ Svt’
Bunk

[Coffinmaker]

Hey Bunk,

Let us compare notes.  Tralalalalalalalala    Now, I do have a recipe.  It works quite well  FOR ME!!  I am also using a mix'd lot of dies.  They are all somewhat dedicated.  I load on a Dillon 650 with all the safety bells and whistles.  I have a reason for all those safety bells and whistles ........ I'd rather not discuss,..... nor admit to.
Y'all know I run APP.  I also run BP.  I run both thru a Dillon Powder Measure.  Only thing I "dip" is 12Ga Brass Hulls.  But, that is a different subject. 

For the C45S I use a standard Dillon 45 Colt resize die.  A Redding 45 Auto Rim Seating die and a Redding 45 Auto Rim Crimping die.
I wash my cases in 50/50 water/Vinegar.  Dry and tumble.  De-Prime when I reload.  I neck size only.  Full case of APP 2f, Federal LP Primer.  Special 130Gr bullet called a "Barnstormer" for pistols.  160Gr RNFP For the Rifles.  I get just a tad of Blow-By.  Not enough to bother with and I shoot complete match without having to mess with the Carrier Block.
Because the Auto Rim has a smaller Neck Diameter, I get a real FRIM Crimp.  ALL of my rifles (4 Henry 1 '73) in 45 have very "Generous"
chamber dimensions.  I think they'd Blow-By with 105 Howitzer rounds.  But the Blow-by is managed.
YMMV

Coffinmaker

PS:  I run a full case of APP, to the base of the bullet.  I have no idea just exactly how much powder it is.  I don't care.  It is the "correct" amount volumetrically and it works.  What it weighs??  Meh.

[Noz]

OK OK OK OK ....... MY TURN ... MY TURN ....... DDD is correct as confirmed by his pal Smedley.  The wall thickness and neck thickness of the C45S case is a smudge thinner than the usual 45 Colt.  The result is better obturation (expansion) of the case and case mouth in the chamber for a better gas seal.  Less Blow-By.  A good thing.

Now let us address some common miss-conceptions.  #1.  You can resize with 45 ACP dies.  No you can't.  Well, you can, but you shoot yourself in the foot by doing so.  As NOZ has found out the hard way.  45 ACP neck diameter is .473 and the base is .476  You should note, that is a tapered case.  Not actually straight walled.  So you have sized the C45S case to a taper.  Not a good plan, because .......
The 45 Colt case is bigger.  A lot bigger.  Neck is .480 and the base is .480.  Let us extrapolate.  You may have an oversize chamber (most likely with a rifle) and a .480 Case won't expand to seal it.  So, you take a C45S case a size it even smaller.  No way it can seal.  You get massive amounts of blow-by.
Normally, I try not to be too contrary (if your believe that ......) but contrary to some miss-guided golden information, you CANNOT SUCCESSFULLY load/reload C45S with a set of 45 ACP dies.  So put that cost saving idea smooth out of your mind, unless your dead set on ruining all your C45S cases.  Roll crimp.  Roll crimp FIRMLY.

Some suggestions.  45s generate Blow-by.  PERIOD.  It can be mitigated.  Eliminated??  Probably not.  The problem is really bigger in rifles than in revolvers.  With the C45S cases actually being a mite thinner (no, I don't know how much) and perhaps a mite softer, they do obturate better and you get less blow-by.  Further ....... Neck Size only.  Neck size to the depth of the given bullet you are using and leave the rest of the case alone.  Your results with revolvers will be really good.  Rifles???  I take no responsibility at all.  Rifles have chambers all over the place.  Almost NONE of which are at the tight end of SAMMI.

Coffinmaker

I had figured that out and have a set of 45 Cot dies. Just haven't gotten back to them.