seating depth and dies

Status
Not open for further replies.
R

remmag

Member
Joined
Jan 3, 2010
Messages
207
hey there
i have been loading a batch of 45 auto with missouri bullet co 200 grain lswc bulluts
and with a rcbs press ,lee seating die and as uniform of a pull as i can i keep getting different caol measurements

after examining everything i think i may have found the problem but not sure , also i am not sure how to fix it

my lee die seems to be made for a round nose bullet, the part of the die that pushes the bullet is rounded , the end of my lswc bullets are flat, i would think this would be the weak link or the best possible spot in the set up for inconsistancy

are there certain dies you guys recommend for flat nose bullets, am i barking up the wrong tree

do i need to change from lee dies

how much defference in coal is tollerable from a safety stand point

thanks for your help
 
What are the differences in your COL measurements? Not sure about Lee, but I think all the others have different styles of seating plugs available.
 
from 1.264 to 1.271 most average 1.267

is this too much varience

i checked on mudway and they dont carry seater plugs for lee, wondering if i should try redding, they do have different seater plugs for those

thanks
 
If seater plugs are a necessity then Lee would make them....I'm just saying...

Beauty of machining is the consistency...even if the dies are rn only...once they are set the oal is set and should consistent bc the machining will not change. Each shape may require a different setting but once set it's set for that specific shape.

I may have that wrong but it makes sense to me.....
 
they dont seem to be shaving lead, i have the case mouth expanded only enough to accept the bullet though. as for now i am ok with it if it is safe

i do want to be better and more precise though

i should note that the recipe i am using from lyman 49th for 200 grain #2 alloy show s coal at 1.235,

i was trying to set up the die to have a measurement of (i beleive .947 from the shoulder of the bullet to the bottom of the case. i left my paper in the garage. that is why my coal is longer than the above published data
 
Check the bullet from its base to the nose. How much difference is there between bullets. Each bullet is cast in a different cavity that may be a different size. I feel your Ok, as your are.
 
Isn't everything? Just keep reading, asking questions, trying things, and before you know it, you'll be an expert. :)
 
i measured them and they are consistant to within .003

thanks for all of your help
 
.005 max variance? Just seat bullets and put the calipers down. Nothing to stress about. Just the nature of the beast. Nothing wrong with the equipment or dies.

Most seating punches are concave. This is to help with the centering of the bullet. A slight variation in the bullet will bring about a slight variation in the OAL. The punch doesn't contact the flat end of the bullet. Yes, bullets vary some.

how much defference in coal is tollerable from a safety stand point
Click to expand...

No safety issue here with a tolerance of 5 thousanths. As long as you are not near a max load there is not much chance a little difference in seating depth is going to send you into extreme pressure ranges. Yes, seating depth will change the pressure, But there is quite a latitude of seating depth you can use without getting into trouble.

You can use the recipe COL and see how your gun likes it. If it will feed, fine, then you are good to go. If it doesn't feed, try going a little shorter, but something like .020 may make a difference where .005 would go un-noticed.

Have you shot any of those 200 gr bullets? I tried some and had to up the powder charge quite a bit to get them to reliably cycle the gun. Don't load the whole batch until you try them, or you may be disappointed. Playing with the powder charge solved the problem in my tests. If that had not turned the trick I would have played with the seating depth.

Remember the rule of working up a new load: Start low and work up. I like to load 5 of one load near the low end, then increase it a bit and load 5 more, and do that with at least 4 and maybe 5 loads then go shoot. (bag and label the loads) Somewhere in that group should be a load that cycles the gun and has no signs of overpressure. Now you can load up a batch and be confident that they are going to cycle the gun and not be overpressure.
 
james
thanks for the respnce
i did load the same load once before and the gun cycled great
i guess i am trying to be too detailed,
i know what you mean about the gun not cycling well , i tried the starting load with unique and the gun wouldnt cycle

thanks again
 
Trying to be detailed and precise is good, but the variances in bullets, neck tension, seating stem fit, etc make it impossible to get every O.A.L. exactly the same. Sometimes on some loads I will beat a .005 spread on O.A.L., but if I am at .005 or less I am happy. I loaded a small batch of Precision 200 Gr SWC's Saturday night. Many were right at 1.262, but they all fell within 1.260 to 1.265, except for one little rascal that came in at 1.259. Same as the small batch I did Friday night.
 
Head to Shoulder measurement-45acp-.947"

I was trying to set up the die to have a measurement of (i beleive) .947" from the shoulder of the bullet to the bottom of the case
Click to expand...
The measurement to the shoulder is more accurate. The bullets length will change with different alloys.(home cast). If the shoulder contacts the rifling, you want the head to shoulder measurement to always be the same. Less end play, better accuracy for slow fire. The shoulder contacting the rifling, not so good for rapid fire, depending on how hard the alloy is. Soft lead is more forgiving. 45acp947inch_001.jpg The .947" can be adjusted to fit your firearm, may not work in all at this length. :)
 
Some dies (Dillon, Hornady, etc) do come with separate seating anvils for different nose shapes. If SWC bullets are all you ever shoot, then you might gain something by modifying your anvil to flat. Any machinist can make quick work of that task.

If you decide you want that done, and can't find anyone t help you out, drop me a PM.
 
My Lee dies give around 0.015" max spread with certain flat nosed bullets. I don't sweat it.
 
Status
Not open for further replies.

Similar threads

R
  • Locked
need die advice
Replies
11
Views
820
remmag
R
R
  • Locked
inconsistant seating depth
Replies
13
Views
922
rcmodel
R
B
  • Locked
Seating depth variation and dies
2 3
Replies
52
Views
1K
Skgreen
S
wiiawiwb
  • Locked
Seating die plug for flat nose bullet 45LC
Replies
7
Views
3K
Blue68f100
Blue68f100
B
  • Locked
Redding competition seating die - is this statement true?
Replies
22
Views
4K
fguffey
F
Back
Top