Since the bullets already have a cannalure, I would give them a light crimp with the FCD.
Regular SMKs with no cannalure… I don’t crimp… Although I’ve shot good Factory Match ammo that had a factory crimp on it… Specifically WIN RA223M which has 69 grain SMKs.
If you’re running a regular old sizing die with an expander ball… you’re probably not going to realize any difference. It’ll be decent, accurate ammo either way.
The Dillon 1050 has a station (the backup rod for the swager) that adds a slight bell at the end of the case mouth before the bullets are seated. I finish up with a light taper crimp to get the loaded case mouth back to .246".
This step (unless the unit is removed), takes sized brass from from .244" to .250" at the case mouth. This seems like a lot, but the 77 SMK bullets work better for me with this step than without. Possibly it’s on the same principle as a neck expander (M?) die, but I don’t know.
Seating the 77 SMKs in a single stage press I can feel a big difference in the force required to seat. Without the belling/expanding step I’ve even pulled a 77 gr bullet and seen some jacket damage at the upper edge of the boat-tail.
Has anyone played with this operation on a 1050 (other than just removing)- possibly backing off on the backup rod to produce a smaller bell?
I don’t crimp and from the research I did before deciding not I didn’t find any reports from actual shooters that experienced any bullet setback or other issues from not crimping.
That’s specific to each loader and his equipment. There’s a ton of variables to consider. But I agree that set back is rare. I find set back rounds at the range all the time. But those rounds were factory crimped and were a weapon problem, not an ammo problem.
For bulk practice ammo, there’s no downside to crimping. And the position is there on the progressive for me. So I put a light factory crimp when running regular bulk 55 gr FMJs.
No crimp is needed, however upon doing a little accuracy testiing I found my precision 75gr and 77gr loads shot better with a very light crimp from the Lee FCD. Best thing to do is load em up a few different ways and check em…shoot em to see what works best.
I also found the same results with my 168gr SMK .308 loads where a very light crimp from the Lee FCD seemed to make my groups more consistant/together.
sinister/others-
i’ve got a set of full length ‘s’ type redding sizing dies w/competition seating die coming, just not here yet. what is the std size bushing that comes with that die set? midway’s description says it’s ‘std’ size, just not sure what the decimal is. i’m trying to avoid crimping as well, for use in a noveske spr chamber, and want to get a selection of bushings on the way, if the right one’s not included with original die set. thx for any replies.
For what gun and what caliber?
From what I read, and tried… you want to measure the Outer Diameter of your loaded ammo and pick a bushing that is .001 smaller for bolt gun, and .002 smaller for auto loader.
I bought the Full length S die for .308 and picked a .330 bushing because my loaded ammo was trending around .332" at the case mouth.
Mark.
18" noveske spr. .223/5.56mm. some hornady 75gr factory i’ve got are .250od. i’ve got about 600 of the 75gr hornadys to play with, so sounds like a .248-9 bushing might work. .245 would make for a snug fit, which i’d prefer to crimping. i’ll get around to playing with a sampling of all and determine what works best in this gun, once i’ve fired up the reloading dies, etc. i’ll eventually inside/outside ream some of the brass i’m attempting to really hammer for accuracy, which should yield a result with a consistent neck fit, but again, it’ll all come down to the shooting to see if theory bears out.
This is what I have learned.
Interesting topic and lots of opinions and info here. I started loading Hornaday 55gr FMJs for my AR earlier this year and never crimped, then recently started using my Lee crimp die, setup to just barely touch the cases.
I’ll have to do some accuracy testing between crimped and non crimped and see what holds out for me. I’d be interested to see what you guys discover through range testing as well.
Yeah… I’ve noticed that I get varying neck tension when seating my 308 bullets using the Forster Benchrest Die. I mean… you can feel it at the press arm.
I wonder if a slight crimp wouldn’t make the neck tension a little more consistent between rounds.