Click on the image above to learn more about the M1 Carbine
|
Bullet Setback |
Post Reply |
Author | |
kwesi1
Recruit Joined: Oct 13 2018 Location: Texas Status: Offline Points: 27 |
Post Options
Thanks(0)
Posted: Oct 20 2018 at 11:34am |
I purchased some Speer #1895 Varmit 110 HP’s. They do have a cannelure for a roll crimp for revolvers. Speer’s 39 Carbine Load Data has it seated above the roll crimp area. I loaded a dummy round. After chambering there was setback. I’ve learned over the years that applying more and more crimp is not the correct solution. I’m expanding the case ever so slightly and plan to load the bullet 5-10/1,000 longer to adjust for the measured setback then apply normal crimp (not much). Anyone else experienced this with this exact bullet or any 110 grain FMJ? Thoughts or other suggestions?
|
|
floydthecat
Hard Corps Joined: Oct 13 2016 Location: Mississippi Status: Offline Points: 1996 |
Post Options
Thanks(0)
|
Maximum OAL is 1.680. Other than a long OAL, seems to me that bullet profile would be the only reason for the bullet to be contacting the bore. I am just guessing your OAL is long. I'd ignore the cannelure and seat the projectile where it will properly chamber. I hope the gun will chamber hollow-points?
|
|
kwesi1
Recruit Joined: Oct 13 2018 Location: Texas Status: Offline Points: 27 |
Post Options
Thanks(0)
|
The COAL in 1.635 (Speer for this bullet). My dummy round chambered and has setback.
|
|
floydthecat
Hard Corps Joined: Oct 13 2016 Location: Mississippi Status: Offline Points: 1996 |
Post Options
Thanks(0)
|
The carbine chamber starts to taper at 1.300 and continues to taper (the throat) out to 1.4452 at which point you encounter the bore. Your OAL being well within spec....it just about has to be the profile of your projectile. The nose of a spec. FMJ will "reach" into the bore without contact. I am not familiar with the projectile you mention, but it may be broad enough at the nose to contact the bore? Just my uneducated guess. Continue to seat your dummy round until set-back disappears. If you can do that and make it work, you may have to adjust your charge accordingly to account for the deeper seat, if you take it very deep. Honestly, I have experimented with alternative profiles other than the military ball and have failed to achieve reliable feeding in most cases. If you stray too far from Mil-Spec FMJ, troubles may follow. I only load FMJ or JLRN that has the same profile as FMJ.
|
|
kwesi1
Recruit Joined: Oct 13 2018 Location: Texas Status: Offline Points: 27 |
Post Options
Thanks(0)
|
Setback eliminated update: I loaded another dummy round WITHOUT expanding the case mouth. Even after 3 chambering the bullet did not move.
|
|
floydthecat
Hard Corps Joined: Oct 13 2016 Location: Mississippi Status: Offline Points: 1996 |
Post Options
Thanks(0)
|
If you can seat a bullet without expanding the case-mouth, that surely increases case-tension, which is what holds the bullet in place.
|
|
kwesi1
Recruit Joined: Oct 13 2018 Location: Texas Status: Offline Points: 27 |
Post Options
Thanks(0)
|
Absolutely but it’s a slow process. I set my seating die @1.635 to create the dummy round. I loaded three ladders this eve with the load data Speer provides:
H110 13.0 gr , 13.5 gr and 14.0 gr CCI 450 SR (magnum) 1.635 Speer 110 HP Varmit round Fiocchi & PPU fired brass Brass trimmed to 1.683 These bullets seem to have some slight variances. My COAL’s ranged 1.630-1.640. I’m hoping this project will yield an accurate hog round. |
|
floydthecat
Hard Corps Joined: Oct 13 2016 Location: Mississippi Status: Offline Points: 1996 |
Post Options
Thanks(0)
|
14 grains of H110 and an OAL of 1.680 nets 1900fps on my chronograph, which is right where it needs to be for a 110-gr. FMJ. If you're loading a hollow-point, 1.635 OAL is likely about right. 13.5 grains nets around 1850fps and cycles my carbines very well. Doesn't seem to make any difference where it prints on the target using 13.5 or 14.
|
|
kwesi1
Recruit Joined: Oct 13 2018 Location: Texas Status: Offline Points: 27 |
Post Options
Thanks(0)
|
Speer data for their HP:
12.0 gr @ 1607 14.0 gr @ 1905 |
|
floydthecat
Hard Corps Joined: Oct 13 2016 Location: Mississippi Status: Offline Points: 1996 |
Post Options
Thanks(0)
|
Looks like 14 may be your ticket. The original performance data listed 1900fps and 36,500 for the pressure as I recall. Since your carbine passes on the no-go gauge....you have a nice tight little gun with lots of life left in it. ENJOY!
|
|
kwesi1
Recruit Joined: Oct 13 2018 Location: Texas Status: Offline Points: 27 |
Post Options
Thanks(0)
|
Thanks.
|
|
Post Reply | |
Forum Jump | Forum Permissions You cannot post new topics in this forum You cannot reply to topics in this forum You cannot delete your posts in this forum You cannot edit your posts in this forum You cannot create polls in this forum You can vote in polls in this forum |