[swifty]

This afternoon, I shoot about 20 rounds with 5744 30 grains
and had two misfires with federal large rifle primers. I rechambered thede rounds and they fired properly. I did notice some unburned powder in my rifle barrel.
I have using the RCBS priming unit that fits on my Rock Chucker with a primer tube feed.
Now i am beging to question the powder 5744 , partial fill,
priming technique,bullet crimping( used the Lee crimp).
Also, I got some erratic velocities on my Pact chronograph.
The volicities ranged from 1270 feet per second to 680 feet per second.
I have used the same chronograph before with consistant velocities. I shoot several rounds with my 375 H7H mag
whic seemed to be consistant.
I called Accurate powder company on Friday.They assured me that 5744 would perform properly with a partil filled cartridge.
The rounds printed well on a 50 yard target.Its just that I got some misfires, unburned powder, and eratic velocities.
Comments or answers will be appreciated.

 

[Alk8944]

swifty,

The mis-fires and erratic velocities can both be attributed to a light hammer strike, Yes, it does matter how hard the primer is struck, a too light strike can result in poor ignition even if the cartridge fires. I would check firing pin protrusion, and also make sure that there is no unburned powder or other obstruction in the bolt.

Don't worry about the 5744, it is one of the best choices for lead bullet loads in the straight cases.

If it was a cold day, excessive lube in the bolt body cloud have been a problem also.

 

[IDShooter]

Swifty,
I've used the 5744 without any problems, either with ignition or consistency. It DOES leave a bit of powder residue, but that has never caused any difficulty for me.
I would look for causes other than the powder. Inconsistently seated primers and inconsistent firing pin strike seem like the most likely culprits for misfires. Wide velocity spread can be the result of those, as well as inconsistent crimp.
Hope you get it straightened out!
BTW - I LOVE the smell of 5744 when it's fired. It doesn't smell like any other powder I've used. I know, I'm goofy!

IDShooter

 

[Bill M]

HI Swifty,
From your post it sounds like the problem could be almost anywhere. Your symptoms are vague enough that they could spell trouble or simply be part of the deal with that load. Here is my suggested path to resolution.

1.. Reload more of the same ammo making sure of clean primer pockets, fully seated primers and a heavy Factory crimp. Natually all safe and proper reloading procedures also. WHAT BULLET ARE YOU SHOOTING???

2.. Get some factory ammo similiar to the reload above

3.. Clean the chamber of your gun

4.. Test fire in conditions favorable to the chrono (sorry, you probably already know this). Mine likes sunny days with the chrono in the shade but looking up at a bright sky. Poor light and a couple of other factors (like cold) can really cause a chrono to give you false results.

5. Shoot the reloads and factory loads and compare the results. You might want to take your 375 just to make sure the chrono is telling you the truth.

6.. Let us know the results. Hopefully this will tell you where the problem lies though, by itself, it may not reveal the problem. At least it can be narrowed down and finally discovered.

Best................ Bill M

 

[Big Bore]

Quite often what you described can be caused by one of three things. Gun related, gunk aroung the firing pin slowing it down. Often, it will fire the second time, firing pin strikes usually look very light.
The next are reloading problems, as was mentioned, when you see the gun go snap, the first time, then boom the second, and this happens several times, I suspect two things. One, the primer pockets were not cleaned or two, the primers were not seated all the way into the bottom of the primer pocket. The first hammer strike seats the primer all the way. If you look at the primer after the first strike, it will appear light. Then try it again and it goes boom, the primer strike will look normal. The build up of crud in a dirty primer pocket cushions the first blow, but is compacted by it so that it will fire the second time. Either condition gives exactly the same indications. If you do not clean primer pockets, start. If you seat primers with the press mounted arm, you might want to get a hand primer or a bench mounted priming tool so that you can feel the primers contact the bottom of the pocket. I bet that cures the problem. Good luck.

 

[Gunnut45/454]

swifty
You said they fire the second time they struck by the firng pin? What did the primer look like after the first strike? If they were barely imprinted by the pin 1. Primers were not fully seated. 2 If they were imprint like a normal fire round -but didn't fire -primer could have been cracked(primer compound).3. Firing pin is either dirty-or spring is weak! Good luck hope this helps.

 

[swifty]

misfires and problems with the 45-70

I called Pact the fokes that made my new chronograph.
They suggested change the battry.I did and the problems of erratic readings cleared.It was a new battry that was removed,
but it was failing.
I called accurate powder, they said unburned powder was not unusal for 5744.
I can only relate the misfires to improper primer seating.
I do think I am going to switch to Federal mag primers 215.
I was using 5744 in amounts of 27,30 and 33 grains for a remington jacketed 405 grain bullet. I was averaging 1250 for the 27 grains, 1340 for 30 grains, and about 1450 for 33 grains. They all seem low but fairly consistant.
We will see what the Federal's 215 will do.