PDA

View Full Version : IMR 4895 leaves unburnt kernals in 308 barrel



gunnmakr45624
09-24-2020, 04:55 PM
I have searched but have not found anything that seems to give a satisfactory answer.
308 24 inch bull barrel
311466 cast bullet sized 309.5
IMR 4895
28.5 grains
Set at 2. 510 length which is 15 thou off lands.
Number of unburnt powder grains in barrel.
Better to up the powder grains or reduce powder charge?

gunnmakr45624
09-25-2020, 10:36 AM
Thank you all for your wonderful responses to a beginners questions!
Was told what a great site this was. What a great disappointment!!
Will not ever ask a question again, thanks for making my day

gunnmakr45624

popper
09-25-2020, 10:44 AM
Way too low a load!! Try 37gr or change to different powder. IMR is NOT the same as H - which CAN be downloaded. Sometimes it takes a while to respond.

swheeler
09-25-2020, 10:45 AM
28.5 grains of IMR 4895 isn't operating at enough pressure in your 308 with that light of cast bullet(150gr) to burn completely. If you must use IMR 4895 you need a filler like kapok. Just relax and calm down you will get answers, people need time and most never even saw your post like me till just now.

Larry Gibson
09-25-2020, 10:49 AM
A little quick on the trigger there......only saw your post this morning.

With the lighter weight 411466 in the 308W the IMR4895 is not getting up to sufficient psi to burn "clean". Additionally, there could be ignition inconsistencies from variation of the powder positioning. To alleviate the problem, if IMR4895 is going to be used, I suggest you use a dacron filler. I've shot thousands of 311466s in my 30 cal rifles [308Ws and 30-06s] over IMR4895 with excellent accuracy and pretty much "clean" burning. The dacron filler will also give more consistent ignition and consistent burn which most often promotes better accuracy. Try 28 - 30 gr IMR4895 with a dacron filler with your 311466.

If you're not familiar with the use of dacron as a filler check out; http://castboolits.gunloads.com/showthread.php?109280-The-proper-use-of-fillers

DougGuy
09-25-2020, 11:14 AM
Thank you all for your wonderful responses to a beginners questions!
Was told what a great site this was. What a great disappointment!!
Will not ever ask a question again, thanks for making my day

gunnmakr45624

I would further oblige you sir but the word filter will catch it and you won't get the message of "thanks." That's alright, if you come in here like somebody owes you something, you can leave the same way. Good riddance.

My 180gr plain base sits over 41.5gr H4895 and goes 3 into a GUITAR PICK @200yds. HAVE A NICE DAY!

sharps4590
09-25-2020, 02:10 PM
A bit impatient, are we?

charlie b
09-25-2020, 05:51 PM
^^Kind of an understatement?

I fired quite of bit of IMR4895 with the Lee 180gn bullet. It did fairly well with 30.0gn. No fillers. No unburnt powder. I also like to seat my cast bullets (powder coated) so they are a bit of a jam fit into the rifling.

Gtek
09-25-2020, 06:22 PM
Snowflakes with guns, lions, tigers and bears OH MY!

fastdadio
09-25-2020, 07:57 PM
Joined almost 5 years ago, and that's his intro.... I looked at his profile page and noticed something interesting, it says;

gunnmakr45624
has not made any friends yet.

John Boy
09-25-2020, 08:29 PM
Gunmakr, since you are dissatisfied with real time responses to your post , recommendation ... buy a reloading manual and read it to answer your own questions.
PS ... Goodbye

jimb16
09-26-2020, 09:31 PM
One might also ask if he is putting any kind of crimp on the bullets or just using neck pressure. That can have a big impact on burning as well.

Lloyd Smale
09-28-2020, 05:55 AM
its probably not unburned powder. Its inert material (filler) they add to powder to control burn rate. Have a bit of patients though. People here will help you.

Shopdog
09-28-2020, 07:33 AM
Check your loaded neck to chamber clearance. You can play with bullet diameter towards that end. What happens with a full "jam"? Have you tried different case,"neck tension"? What is the accuracy now..... and what are you looking for?

Understand the frustration with,not just this forum but in general. We're not all on the same frequency WRT question to response "time" or sincerity. Just calm out,take a big hit of lead fumes(jk) and put your head down in the loading room..... if all that doesn't work,add more powder.

303Guy
09-28-2020, 03:51 PM
It looks like gunmakr isn't coming back. But on his question, does it matter if there is unburned powder? Or partially burned powder. My uncle was an armorer in WWII in Africa and he told me how after a machinegun shoot with 50 Brownings, they would sweep up buckets of unburned powder from in front of the firing line.

Anyway, I used to use a particular powder for my 44 mag and it burned clean while others had unburned kernels in the bore. This same powder did it with the 357 mag but increasing the powder charge would solve that. Also, firing the same loads in a rifle would burn it clean.