9mm not passing plunk test but chambers and extracts just fine. Tearing my hair out!!!
- Thread starter bhhacker
- Start date
- Status
The old Lyman manual I have saved on my work computer says that 4 grains of Unique should be a reasonable starting load. You might not get 100% reliability with a light load depending on the gun it's being used in, but it's probably a decent place to start.
LiveLife
Member
So with 0.539" bullet length and 1.050" OAL, I get:
1.050" - 0.539" = 0.511" as max case fill
Using .751" average resized case length, I get:
0.751" - 0.511" = 0.240" below case mouth
Marking inside of case and filling with Unique, I get 4.5 gr. So you don't have to worry about powder compression until 4.5 gr.
I have a feeling you will get best accuracy with 4.6 gr load.
1.050" - 0.539" = 0.511" as max case fill
Using .751" average resized case length, I get:
0.751" - 0.511" = 0.240" below case mouth
Marking inside of case and filling with Unique, I get 4.5 gr. So you don't have to worry about powder compression until 4.5 gr.
2004 Alliant load data lists 4.9 gr as max charge for 125 gr FMJ loaded to 1.150" and 10% reduction is around 4.4 gr and .2-.3 gr reduction for using shorter OAL is 4.1-4.2 gr as start charge - http://www.thehighroad.org/attachment.php?attachmentid=182147&d=1364769070
Since Unique burns more efficiently at higher charges, I would test 4.2, 4.4 and 4.6 gr as fluffy Unique can withstand slight powder compression. Even using short 1.050" OAL at 4.6 gr, I believe you will be below max listed pressures.
I have a feeling you will get best accuracy with 4.6 gr load.
Last edited:
jmorris
Member
- Joined
- Sep 30, 2005
- Messages
- 24,267
I find it easiest to just start at the beginning.
Do you have factory ammunition for the firearm?
If so, does it pass the test you are doing?
If Yes, when you size and deprime a case does it pass the test you are doing?
Just getting to that point eliminates a lot, then we can move on to expanding, seating, OAL, crimping and such.
fxvr5
Member
- Joined
- May 26, 2017
- Messages
- 3,285
Rarely. If you use a die that seats and crimps at the same time, this can happen. If you use separate dies for seating and crimping, bulges appearing elsewhere are rare and hard to produce.
At the very least, remove the bell. A case that still has a belled mouth, even the slightest amount, can prevent it from chambering.
My load development testing included tests on different crimp measurements. I actually got pretty good accuracy with crimped rounds but it was a fight which included different bullet lengths, ogive, case lengths and bullet diameter. When loading .356 diameter bullets, I flared the mouth of the case to .379, seated and crimp to .378. For .355 bullets, flare to .378 and seat, crimp to .377. While this works, you still have to manage or deal with brass length variations that changed my preferred measurements.
My resizing die leaves the mouth of the case at .372. I bevel the mouth and flare to .375 or .376 and seat the bullet, no crimp. After testing for bullet set back while cycling these rounds, I had no issues. Speed increased on the non crimped rounds at most 20 fps. My gun likes 1150 -1170 fps so a slight adjustment and these rounds are more accurate than the crimped rounds at the same speed.
I use a Caldwell Rock rest setup on a bench and shoot at 25 yards, for testing rounds in my glock 34.
On a side note, I waisted a lot of components til I learned a good way confirm I'm using good straight brass. Roll the resized cases on the bench. If it wobbles and you can see light between the case and bench top, you're not going to get the best accuracy with bent brass. I have new Winchester brass that is crap (bent) and not worth loading.
My resizing die leaves the mouth of the case at .372. I bevel the mouth and flare to .375 or .376 and seat the bullet, no crimp. After testing for bullet set back while cycling these rounds, I had no issues. Speed increased on the non crimped rounds at most 20 fps. My gun likes 1150 -1170 fps so a slight adjustment and these rounds are more accurate than the crimped rounds at the same speed.
I use a Caldwell Rock rest setup on a bench and shoot at 25 yards, for testing rounds in my glock 34.
On a side note, I waisted a lot of components til I learned a good way confirm I'm using good straight brass. Roll the resized cases on the bench. If it wobbles and you can see light between the case and bench top, you're not going to get the best accuracy with bent brass. I have new Winchester brass that is crap (bent) and not worth loading.
fxvr5
Member
- Joined
- May 26, 2017
- Messages
- 3,285
By bent brass do you mean the brass is damaged and defective, or the bullet is not seated straight and that is producing an asymmetrical bulge in the brass?
LiveLife
Member
OP, now that you determined the working OAL and established a start charge, as an added insurance, you should check bullet setback of your rounds.
Load some dummy rounds (no powder, no primer) and feed them from the magazine and release the slide without riding it. Measure OAL before/after and bullet setback of a few thousandths is OK but significant bullet setback of more than .005" can add to pressure issues.
Load some dummy rounds (no powder, no primer) and feed them from the magazine and release the slide without riding it. Measure OAL before/after and bullet setback of a few thousandths is OK but significant bullet setback of more than .005" can add to pressure issues.
Last edited:
Blue68f100
Member
This is the reason to workup your load with the OAL you plan to use. Lyman has published warnings on setback, where a 0.020" setback with Tightgroup can run the pressure over 60k psi, normal 24k psi. The reason this powder has KBOOM handguns quite regularly till this got out. Most fast burn powders get spiky/moody at the top end. With medium and slow burn rate powders are not near as sensitive. But as you shorten the OAL the pressures does go up. To what level, it would require pressure testing equipment to determine. Quick load may predict it if all the info is entered.
Basic handloading requires us to determine what OAL we require for our gun to function properly .This gives us our OAL based on the bullet we choose. Once we have this info we pick a powder. Now looking at published data will tell you a load range based on what the mfg used for OAL. So if our OAL is less we must reduce the charge appropriately to avoid over pressure conditions. Then you should work the load up from the low starting point looking for pressure signs and accuracy. If shooting competition where your required to meet a PF, you have to check the velocity to get that number with your bullet. Just picking a middle of the road charge is not a good or recommended practice particularly is your OAL is shorter than published data. Depending on your powder choice you may get into compressed loads. Compressed loads are ok provided you worked up to this. It only applies with what you tested with. So using mixed brass will require you to workup with each, since they have different volume.
The down side is that primers are a poor indicator of pressure. If your showing over pressure signs you way over since primers will handle about twice the pressure a handgun produce. Using a crony will help you determine if your getting into dangerous conditions. Reading the brass is basicly all we have to go on. One of the reason mfg use new brass. Then brass work hardens as it's worked so it gets stronger making the pressure signs higher for they to show up.
Using bullet profile to determine OAL when a bullet change is made for me is not a good practice. Way too many variables your dealing with. Yes it will tell you that you will be longer or shorter but it does not tell you what the pressures will due. Bullet jump plays a very important part in pressure. The closer you get to the lands/leads the quicker the pressure will rise. So it's always best to start over on working up your load.
My 0.02 cents on all this bickering/discussions
Basic handloading requires us to determine what OAL we require for our gun to function properly .This gives us our OAL based on the bullet we choose. Once we have this info we pick a powder. Now looking at published data will tell you a load range based on what the mfg used for OAL. So if our OAL is less we must reduce the charge appropriately to avoid over pressure conditions. Then you should work the load up from the low starting point looking for pressure signs and accuracy. If shooting competition where your required to meet a PF, you have to check the velocity to get that number with your bullet. Just picking a middle of the road charge is not a good or recommended practice particularly is your OAL is shorter than published data. Depending on your powder choice you may get into compressed loads. Compressed loads are ok provided you worked up to this. It only applies with what you tested with. So using mixed brass will require you to workup with each, since they have different volume.
The down side is that primers are a poor indicator of pressure. If your showing over pressure signs you way over since primers will handle about twice the pressure a handgun produce. Using a crony will help you determine if your getting into dangerous conditions. Reading the brass is basicly all we have to go on. One of the reason mfg use new brass. Then brass work hardens as it's worked so it gets stronger making the pressure signs higher for they to show up.
Using bullet profile to determine OAL when a bullet change is made for me is not a good practice. Way too many variables your dealing with. Yes it will tell you that you will be longer or shorter but it does not tell you what the pressures will due. Bullet jump plays a very important part in pressure. The closer you get to the lands/leads the quicker the pressure will rise. So it's always best to start over on working up your load.
My 0.02 cents on all this bickering/discussions
Bent as in when you roll the brass case on a flat surface you can see the mouth of the cases raise off the table and then make contact all in 1 revolution.
fxvr5
Member
- Joined
- May 26, 2017
- Messages
- 3,285
It sounds like you're describing a crooked seating bullet that is producing a bulge in one side of the case. Right?
wrench459
Member
- Joined
- Jul 22, 2017
- Messages
- 188
Sounds almost like a unsupported barrel that fired the round aka glock bulged.
New brass win., well ok don't use them. Your call.
Tcruse
Member
Glade to see you resolved your problem. I have in the past had a similar problem, in my case caused by introducing a new 9mm gun into the mix that has a "tight" chamber. My solution was to use the Lee (sold under some other name) sizing die that is undersized by .001 and setting it to touch the base plate. I stopped using the 4th Lee Factory Crimp Die because it was not useful. I check every round with a size gage (Lyman from Cabelas). I also found that I can back off on the power (CFE/HP48/Titegroup) charge and get the same accuracy. Now, my reloads are happy in the new gun and the existing Glocks (and Baby Eagle). It also turned out that this process catches "cracked" brass that otherwise could have slipped thru visual inspection.
Negative. Brand new Winchester brass. Also found a small number in Starline brass as well. So yes, I now roll all brass, new and range pickup. Straight brass will get loaded and I'll use a brass catcher at the range. I want this brass. Slight wobble brass will get loaded for plinking and does not get picked up after firing.
For consistency, I run new brass through my resizing die so on the 2nd loading and all others, the brass has the same dimensions, neck tension etc.
I did load the Starline brass and shot it in hopes it would reshape, resize and straighten out, no luck.
Last edited:
- Status
