Proper belling and crimping
Quote from Reloader on August 16, 2016, 4:54 pmNew reloader here and I am just setting up my 550B for 9mm. I'm concerned about the vagueness of the bell and crimp stages. (I'm using a Dillon die set.)
1) Decap/resize = no problem
2) powder drop = no problem3) Belling the case - the instruction manual says .020 (twenty thousandths) "should about do it". I wish it was more precise. I'm ending up between .015 and .023 (the inconsistency is an annoyance as well).
The picture in the instruction manual seems to be much smaller than .020.
Q: How critical is this and how can I make it repeatable?
4) Bullet seating. Seems to be ok. My goal for OAL is 1.150 and i'm within .003 consistently.
5) Crimp. How do I know what the proper crimp should be? I've read various measurements that state the measurement at the crimp should be .001 - .002 smaller than the original sized opening.
Q: How critical is this and how can I tell when I have it right? I have pulled some bullets after crimping and I range from no marks to a slight mark to a very visible line on the bullet.
The Bell and the Crimp are really frustrating. I've spent about 4 - 5 hours over the last 2 days just working on that with just a few test bullets and cases.
Final question. How close to the base of the bullet should the powder come? I know this is determined by the powder and bullet size, but is there an unwritten rule such as 'never let the powder touch the bullet when the cartridge is vertical' or 'always make sure there is .001 clearance between the powder and bullet'.
As you can see I like to deal in absolutes. However, it seems that while precision is the goal there are many statements that are quite vague, ie they 'should about do it'.
Thanks.
Than for your help.
New reloader here and I am just setting up my 550B for 9mm. I'm concerned about the vagueness of the bell and crimp stages. (I'm using a Dillon die set.)
1) Decap/resize = no problem
2) powder drop = no problem
3) Belling the case - the instruction manual says .020 (twenty thousandths) "should about do it". I wish it was more precise. I'm ending up between .015 and .023 (the inconsistency is an annoyance as well).
The picture in the instruction manual seems to be much smaller than .020.
Q: How critical is this and how can I make it repeatable?
4) Bullet seating. Seems to be ok. My goal for OAL is 1.150 and i'm within .003 consistently.
5) Crimp. How do I know what the proper crimp should be? I've read various measurements that state the measurement at the crimp should be .001 - .002 smaller than the original sized opening.
Q: How critical is this and how can I tell when I have it right? I have pulled some bullets after crimping and I range from no marks to a slight mark to a very visible line on the bullet.
The Bell and the Crimp are really frustrating. I've spent about 4 - 5 hours over the last 2 days just working on that with just a few test bullets and cases.
Final question. How close to the base of the bullet should the powder come? I know this is determined by the powder and bullet size, but is there an unwritten rule such as 'never let the powder touch the bullet when the cartridge is vertical' or 'always make sure there is .001 clearance between the powder and bullet'.
As you can see I like to deal in absolutes. However, it seems that while precision is the goal there are many statements that are quite vague, ie they 'should about do it'.
Thanks.
Than for your help.
Quote from Reloader on August 25, 2016, 2:57 pmHi,
For belling, using Dillon dies, I do it by feel. Not very scientific I know, but I set it to where I can stand the bullet on the case without falling over, or seating too deeply.
The tolerances you are seeing in your case belling could be due to case length. Typically with 9mm you don't need to worry about trimming cases. However, if you want to have consistent belling then all your cases need to be the exact same length. A case that is a couple of thousands longer will be pushed up further on to the taper and open up more.
For crimping it depends on what type of bullet I'm working with. My plinking rounds are Berry plated bullets so I set my crimp to where it just intends the bullet but doesn't break the plating. You can check this by crimping and then using a bullet puller to separate the case and check what it looks like.
Hope that helps.
Dan
Hi,
For belling, using Dillon dies, I do it by feel. Not very scientific I know, but I set it to where I can stand the bullet on the case without falling over, or seating too deeply.
The tolerances you are seeing in your case belling could be due to case length. Typically with 9mm you don't need to worry about trimming cases. However, if you want to have consistent belling then all your cases need to be the exact same length. A case that is a couple of thousands longer will be pushed up further on to the taper and open up more.
For crimping it depends on what type of bullet I'm working with. My plinking rounds are Berry plated bullets so I set my crimp to where it just intends the bullet but doesn't break the plating. You can check this by crimping and then using a bullet puller to separate the case and check what it looks like.
Hope that helps.
Dan