solving rifle blowback...or...leave well enough alone

[Cheyenne Ranger, 48747L]

I'll condense this: Was using my mentors' first recipe for .45 Colt rounds: 250 gr bullet, 5.5 Red Dot. Life was good and it is a very accurate load for me.

 

Went to PC the bullets: life is still good though I got a lot of weird looks at loading table--Neanderthals

 

decided to 'save 20 gr of lead per bullets so went to 230 gr TC bullets--life is not good now. Got blowback in face, Marlins are known for their generous chambers and mine is probably on the large end of these. Hey, I can fix this!

 

Kept going up on powder--got to point where I was over max load, that's about the time the leading a couple of inches in front of chamber started. Tried tightening crimp to point where even a newbie could tell is was way too much + cleaning out the leading was a real pain

 

So after fighting with this for 6 months I went back to original recipe and life is good. Using the 230 gr TC in pard's 1911 WB loads.

 

Life 'humbles' me on a very regular basis.

 

cr

 

 

 

[Jefro, SASS#69420]

Howdy Ranger, I'm sure you already know the best way to solve blowback in a 45 Colt rifle is to sell it, trade it or keep it, but go ahead and get a 44/40 .......no blowback, not even with BP I know some folks will say bigger bullet, more crimp,more powder, annul heat treat the brass...etc...etc Or just get a 44/40 and fugit about it Glad the original recipe is working for ya........Good Luck

 

Jefro Relax-Enjoy

[Al OVERA, SASS#26238 Life]

If it ain't broke, don't try to fix it!!!!!

Al

[Doc Flimshaw Sass# 73310]

My experience... 200gr. bullet = blowback, 250 grn bullet = no blowback... simple choice

[Tulsey, SASS#11236]

Went through this years ago with my Marlin .45. Ok with 250 grain bullets. With a generous amount of some powders and a heavy scrimp mine was ok with 200 gr, There was no way to stop blow by on anything lighter than 200. The heavier loads of TB seem to work well in reducing blow by.

 

I foolishly forgot about my years ago experience and bought some 185 grain bullets from a local caster, I could live with the blow by, but my brother-in-law tried them in a Rossi and it was so bad he refused to shoot them. A friend has shot them in his Rossi and Rugers with no compaints. Each rifle seems to be a little different.

 

Another thing I found with my Marlin was using a decent load in S&W brass and a 200 grain bullet worked fine.

[Garrison Joe, SASS #60708]

Several things you can do. A friend of mine has a BIG chambered Marlin. I cerrocast it and it has a chamber that mikes 0.486" Wow. 6 thousandths over max chamber.

 

What has worked best for him is the Redding dual-ring sizer.

See thread:

http://www.sassnet.com/forums/index.php?showtopic=250458#entry3271021

He can now shoot 200 grain RNFP and not have too much blowback.

 

As hinted at above, other things can be done

* use a soft slug

* size slug to .454 (this causes chamber pressure to rise very quick, blowing case out to seal better)

* crimp real tight (this causes chamber pressure to rise very quick, blowing case out to seal better)

* anneal the mouth section of the case

* use as fast a powder as possible, Bullseye or Win WST or 700-X (this ALSO causes chamber pressure to rise very quick, blowing case out to seal better)

* if you can't splurge for the dual-ring sizer, you can "neck size" only. Adjust your sizer die so you don't run the case all the way in. Leave bottom half of case unsized. If you only have this one .45 Colt rifle and you don't loan your loads to others, the bottom half of the case will stay "fat" and seal better

* gunsmith can sleeve your chamber to get you down to a tight chamber

* a few pards switch to shooting .44-40 brass in their .45 Colt - that much thinner brass wall in .44-40 works pretty well for sealing the chamber, as opposed to the tank-hull thickness of .45 Colt. At least until someone tries to read head stamps when shagging brass and keeps the brass for a shooter who really has a .44 rifle....

 

 

And switching to .44-40 really is a good solution, if you are willing to do a BIG changeover and use more expensive and fragile brass. .45 Colt was NOT designed to run in a rifle anyway. But I still do it with 200 grain truncated cone, cast soft, hard crimped, with 700-X or WST and the Redding dual-ring sizer. Works for me!

 

Good luck, GJ

[Colorado Coffinmaker]

My take. Blow-by in a 45 Colt case in a rifle is a given. It can be reduced a lot, but probably not completely eliminated.

First suggestion. Shoot your heavy bullet load then neck size only on those cases. See what happens.

Anneal the case mouth. What a groan. I'm too lazy to do that.

As mentioned by Garrison Joe ..... Try 44-40 cases. If you start with new brass, it comes from Starline pretty much straight walled. The 44-40 cases aren't exactly cheap, but it does work.

Last, stay with big heavy bullets and bite the bullet

 

Coffinmaker

 

Forgot: As previously suggested, skip the 45 Colt rifle altogether and save your box tops for a 38-40 or 44-40.

[Griff]

PM sent.

[Chance Ramsay]

I use deleted a 200 gr. Bullet tight crimp a little blow by on marlin still some on yellow boy but most is on 1860 Henry.Like the man said live with it or get 44_40 me I live with it LOL

[Griff]

I use deleted a 200 gr. Bullet tight crimp a little blow by on marlin still some on yellow boy but most is on 1860 Henry.Like the man said live with it or get 44_40 me I live with it LOL

Why we don't post load data on the forum. ½ a what?

[Chuck Would, SASS # 53289]

Why we don't post load data on the forum. ½ a what?

Ahhh, I bet he's got a "barrel" full of bullets from trying that load. <VBG>

[Frog]

Why we don't post load data on the forum. ½ a what?

I'm fairly new to this forum and did wonder why, now I know.

[Augustus Goodnight]

Deleted

[Hans Christian]

Garrison Joe has similar experience to us. We now use the Redding dual ring sizes for both 45 Colt and 38 Special. I tried the neck sizing thing, but with multiple 45 Colt rifles and revolvers, it was a total pain. My Lee FCD was also problematic as I had to clean lube from most every cartridge.

 

Case splits have been dramatically reduced with the Redding die. The finished cartridges don't have that coke bottle look either.

[Warden Callaway]

 

Besides blowing crap back in your face, a lot of crap gets blown back in the action and from there it gets shoved up the magazine tube. I bought the gun used and got the crud along with it.

 

I've converted my Marlin 1894 to C45S. I'm loading a 200 gr bulllet with Unique powder charge. I found the lowest load recommend for 45ACP is as low as you I can go and get reasonably clean burn.

 

I'm now shooting a Marlin 1894 in 32-20. Clean, clean, clean!

[Marauder SASS #13056]

deleted

 

Augustus, that method will certainly reduce the back pressure because it raises the chamber pressure to an unknown level. That is the plus and the concern, we don't know what the pressure of such a load would be.

[Allie Mo, SASS No. 25217]

Please either PM, if you must share your recipe, or refer him to the powder manufacturer's Website.

[Augustus Goodnight]

Please either PM, if you must share your recipe, or refer him to the powder manufacturer's Website.

That's why I didn't put in the number of grains of powder only the bullet weight and type of powder used.

[John Henry Quick]

Howdy Ranger, I'm sure you already know the best way to solve blowback in a 45 Colt rifle is to sell it, trade it or keep it, but go ahead and get a 44/40 .......no blowback, not even with BP I know some folks will say bigger bullet, more crimp,more powder, annul heat treat the brass...etc...etc Or just get a 44/40 and fugit about it Glad the original recipe is working for ya........Good Luck

 

Jefro Relax-Enjoy

 

 

+1

[Chili Pepper Kid, SASS #60463]

I shoot 250gr in the rifle, 200gr in the revolvers. Same powder charge. Mark the 250gr's with a sharpie.

[Moose Wesson]

My experience... 200gr. bullet = blowback, 250 grn bullet = no blowback... simple choice

Bingo!

[Jabez Cowboy,SASS # 50129]

Drop-tube in a case load of 3F Goex compress about 1/8th. of an inch with a bullet weighing between 250 - 270 grains ....

Blow-by ? not so as I notice ...

 

Or just get a .38-40 and call it Mr. Clean ...

 

 

Jabez Cowboy

[Four Eyes Henry]

The brass for the rifle is important too, with starline I get blowback and with CBC hardly any.
I had a sizer die reamed out and now my cartridges are straight walled instead of hour glass shaped.

The rifle is a Rossi '92 in 45 Colt and I'm shooting the J/P 200 grains Big Lube with half a case of Black Powder (filler is cous cous).

[Trailrider #896]

Lot o' foolishness about preventin' blowback in rifles chambered for .45LC. There is a simple solution...do what Winchester did when they found the .45's wouldn't extract well... They invented the .44 WCF!

[Badlands Beady]

I get blowback with my .45 Pedersoli Lightning, but not my .45 Uberti short rifle. Same load, 200gn bullet. ?????

[Nate Kiowa Jones #6765]

Several things you can do. A friend of mine has a BIG chambered Marlin. I cerrocast it and it has a chamber that mikes 0.486" Wow. 6 thousandths over max chamber.

 

..................................................................................

 

 

Good luck, GJ

 

That .486 is still in spec depending on where you measured it. Toward the rear it's dead on. Up front it's only .002 over.

 

This diagram shows both cartridge and chamber dimensions. Please note that unless noted all diameters are +.004 and there .200" inside the chamber the nominal is .4862. if you add .004 to that the chamber can be as large as .4902 and still be in spec. Up front it can still be .484"

45LC CHAMBER AND CARTRIDGE DEMENSIONS

This discussion about the 45lc rifles and the severe blowback with the down loaded CAS ammo comes up almost monthly either on the SASS WIRE or over on the LEVERGUNS.COM forum .

The reason the problem is more common with the 45lc rifle is because the makers all use the maximum SAMMI (Sporting Arms and Ammunition. Manufacturers’ Institute) specs when they ream the chambers for the gun. They do this so the gun will more likely cycle with a broad spectrum of ammo's. This is why semi-auto pistol with match grade barrels tend to be finicky about the ammo they will run. The match grade chambers are tight. The problem is the 45lc chambers are still sized for the old 45lc ammo. Those used bullets as large as .456-7”

 

I believe this all came about when the industry changed from the non-rebated old balloon style cases (like the one in the diagram above) to the modern rebated rim swaged brass. Notice the max bullet dia. .456. Modern 45lc bullets run to only about .454 max with the majority at .452. The current ammo specs don't fill the chambers like the old balloon case ammo. So hard brass and down loaded CAS ammo will exhibit these problems.This 45lc blowby in the rifle problem has been going on for so long now I believe the IMR folks came out with their Trailboss powder just to combat this. A good book charge of Trailboss and a 250 grain bullet crimped well in a Win or Starline case seems to be the solution for some folks. Win or Starline cases are somewhat softer brass than most of the others. Some folks only neck size their once fired rifle brass. For BP, there are some folks using 44-40 brass blown out to 45 and claim it works well. 44-40 brass is really thin.

 

Bottom line is if you want it to stop make more pressure.

[Marauder SASS #13056]

To quote Tim, the Toolman, Taylor,

 

More Power!!! :D

[Awful Close]

Here's the way I conquered the blowback problem in my 45 Marlin.

 

Bought a Marlin in 32-20.

Extremely accurate out of the box, no blowback, and no recoil to speak of.

 

Better hurry, Marlin, Remington, Cerebus,whatever; stopped making them.