View Full Version : .223 Crimp Question
I am currently using Hornady New Dimension Custom-Grade Dies. After much trial and error, I think I have correctly sized my brass (I think in that the brass fits my case gauge, case length has been checked with a caliper,and since I haven't loaded any rounds I haven't had the chance to blow anything up yet). I have loaded a couple of dummy rounds to adjust seating depth and have it set to the cannelure.
My problem is that I have followed the "seating with a crimp" instructions and I'm not sure that I'm crimping at all. It seems that as I make adjustments, I'm only changing the seating depth of the bullet. I don't see any change in the case mouth that would indicate to my inexperienced eye that I'm putting any crimp on. Any advice would be appreciated.
In my limited experience, trying to seat and crimp 223 in one step leads to buckled case shoulders. Following the lead of more experienced reloaders, I went with the Lee Factory Crimp Die, and it was a great choice. It seems to help with accuracy, though to be fair, I had already started using the Lee FCD by the time I started loading for accuracy. Some of the smarter members will be along soon to give advice. :)
That might be what I'll have to do but at this point I'm not sure if I'm even crimping at all.
You may be fine just setting it to desired over all length. Does it feel like you're getting some neck tension when you seat a bullet?
It does. I pressed the bullet against a piece of wood and it took more pressure than I would think a bolt would deliver to get the bullet to seat deeper. Like I said, more pressure than I would THINK. I'm no engineer (like that isn't obvious from my many reloading questions). I just know that bullet seating affects pressure so I want to do everything right.
Try seating then crimping with a Lee FCD. I haven't found the taper crimp seating dies to work all that great. Taper crimps aren't all that noticeable though , so you may be crimping without realizing it. I'd be more worried about COAL than a crimp
What kind of bullets are you using?
I'm using Hornady .55gr fmj boattail with cannelure. The cannelure is what I'm using for seating depth. My dummy rounds I used for adjusting the die came in below max OAL.
They typically will be too short if seating to the cannelure. My bulk 55gr Hornady FMJ loads have ~75% of the cannelure showing when loaded to 2.50" OAL. The cannelure on these bullets are too high if you ask me.
Wouldn't the OAL be dependent on case length? Crap, maybe I don't have my seated die set up correctly after all. I'll have to check again tonight. Does the OAL length have to be exactly 2.50"? I thought the case length was fine as long as it wasn't over max length and didn't have to be precisely the same from case to case unless I was loading precision ammo. I'm still learning
Trim length on 223 should be 1.750. This has nothing to do with finished cartridge oal. Oal should be somewhere in the 2.240-2.255 range depending on bullet. 2.260 is generally considered max for ar magazines. With 55g fmj i generally go for 2.250. Rifle projectiles will have varying oal's by themselves so don't chase your tail if you have a few at 2.250, a few at 2.252, few at 2.248, etc... It's just how rifle bullets are made that cause this.
I'll second the lee fcd. It helps create an even tension on the bullet for consistency. I'm not a fan of seat/crimp in one die.
Measure the outside diameter of the mouth of a resized brass to the nearest 1/1000th of an inch and write down the measurement. Seat the bullet to get the proper C.O.L. by running the cartridge through your seating/crimping die, then measure the outside of the case at the mouth. You should see a reduction in diameter of .001"-'002". If you do not, you will need to adjust the die body farther down into the reloader.
Remove the bullet seater from the die. Turn the die itself ever so slightly into the reloader, tighten the lock ring and run the loaded cartridge through the die again. Measure the case mouth and see if it is smaller in diameter. It may take one or two adjustments before you see any difference. I prefer a .001"-.002" crimp, but you may find better guidance in a reloading manual. After you have the amount of crimp you want, place the loaded cartridge in the die and run the bullet seater back down until it touches the bullet. Tighten the seater lock ring and try loading another cartridge.
Measure the case mouth outside diameter of the next several rounds and compare them to the diameter of resized brass. If you see a difference of .003"-.004", you will have to readjust the die body again. A crimp of .001"-.002" should be enough that you cannot push the bullet back into the brass if you place the bullet tip against a piece of wood and applying pressure by hand.
Ignore the cannelure and load to the correct C.O.L. for your application. You will see some variation in C.O.L. due to the difference in bullet length. I have seen as much as 0.005" difference with bulk bullets, so don't let that throw you off. A bullet comparator is a good tool to determine if you have consistent length from the base of the case to the ogive of the bullet. http://www.midwayusa.com/product/746974/ptg-bullet-comparator-22-24-25-26-28-30-calibers?cm_vc=ProductFinding
Note: I have seen increased accuracy with my bolt action reloads using a light crimp versus just seating the bullet. I believe it gives you more consistent neck tension. The inside of the case neck should be dry, as that also has an effect on neck tension.
Case length and OAL are not related. Seating dies are set to seat a bullet to a given distance from the case head to the ogive of the bullet, not the mouth of the case. This may or may not be when the shell holder touches the bottom of the die. It depends on your press and die setup.
OAL length does not have to be exactly 2.50". 2.260" is the max for mag length ammo, but 2.50" is a happy medium for reliability in feeding.
Do you have a set of calipers?
As Onyx 7 pointed out, case length does not effect C.O.L. As long as the cases are between the trim and maximum lengths, you should be good to go. The Hornady manual indicates .223 cases should be between 1.750" (trim) to 1.760" (max). Cases beyond the maximum recommended length can cause a pressure spike in a tight chamber. The theory is that the case mouth can be crimped even tighter on the projectile when the loaded cartridge is chambered and the increased resistance would cause an unsafe overpressure condition. I got that information out of a Hornady reloading manual and the accompanying illustration supported the theory.
Hornady publishes an excellent set of reloading manuals and I think they are a good investment.
When load in the Hornady 55 fmj to the cannelure you should get a measurement of around 2.200. That is what Hornady recomends, and it functions flawlessly. Some people will load them longer, but I stick with what the factory recomends. That is the great thing about reloading is you get to make that decision based on your needs. Your not just stuck with ammo you bought that only comes one way. Try it both ways and see what works best.
The other have covered the crimping, and how to address that so I won't muddy the waters. With a system like the AR set back is possible but generally the bigger problem is the bullet slipping forward in the case. The AR system acts very much like a kinetic bullet puller. Measure a dummy round and load it a couple times and measure it. It generally will be longer than when it started. Which can lead to over pressure, if you don't have sufficient neck tension/crimp. If you don't have enough neck tension no amount of crimp will help.
It sounds like you have sufficient neck tension, but 1 thing I always do is pull the expander and measure it. It should be .222 give or take a few ten thousandths. If it is to big chuck it in a drill, and spin it in some 1000 grit sand paper. This will take away some material and polish it. Check it often to make sure you don't take off to much. I do this with all my dies where I use the expander, even if there the right size I still do it to polish it.
I would also recommend the Lee factory crimp die. There like 15 dollars, and they are not as sensitive to case length. With the standard crimp die you want your cases to be uniform. The factory crimp die also applies the crimp in a more forgiving manner. If you want to try before you buy let me know. I can send it to you for a couple weeks, and you can just send it back. If your interested let me know. Redding is also making a new taper crimp die that looks very nice. It has a micrometer for adjusting the amount of crimp. It is always better to seat and crimp in two steps. It does add some time if your running a single stage, but it's worth it.
When load in the Hornady 55 fmj to the cannelure you should get a measurement of around 2.200. That is what Hornady recomends, and it functions flawlessly. Some people will load them longer, but I stick with what the factory recomends.
Yep. There are all kinds of factory loads that are much shorter than the spec of 2.250"
Any of y'all ever tried a taper crimp die (Redding or RCBS) as opposed to the Lee FCD? My Lee FCD works fine, but a taper crimp seems like it would be much better for non-cannelured bullets. Less chance for bullet deformation.
Any of y'all ever tried a taper crimp die (Redding or RCBS) as opposed to the Lee FCD?
I've been meaning to try the taper crimp. I have the Die that came in my Dillon set. I just never get around to it. My FCD is set pretty light. You can see a slight crimp when looking at the brass, but it doesn't mash the bullet.
I'd really like to know what the difference between the taper and factory crimp is in accuracy (for me), but it's a bit of a pain in the ass getting the test done.
Digital_Damage
11-17-14, 10:48
I had a lot of issues with the Dillon taper crimp affecting accuracy. it seems to shift the OAL and ogive by crushing the neck down with the bullet.
Any of y'all ever tried a taper crimp die (Redding or RCBS) as opposed to the Lee FCD? My Lee FCD works fine, but a taper crimp seems like it would be much better for non-cannelured bullets. Less chance for bullet deformation.
I have Redding and RCBS dies for .223, .308, 30-06 & 8mm. They have the roll crimp feature and I have been able to load sub MOA ammunition with the .30 caliber dies. I believe that the taper crimp is more suitable for handgun cartridges that headspace off the case mouth.
I would much rather have the Lee FCD for rifle rounds, it only crimps the very top of the mouth. A taper crimp die would to me introduce WAY to much overall neck tension which would be, IMO, a potentially bad thing for a rifle round and lead to potential over pressure issues. I would think a taper crimp die would be a bitch to setup with any sort of "accuracy" with knowing exactly what it was set to. The Lee is EASY to see what its doing and adjust from there depending on what you want.
I agree taper crimp on handgun to take the slight bell out and thats it, easy to see, easy to measure.
I've always set up a taper crimp die based mostly on feel, and secondly on visual. But I agree. The factory crimp die is it. You can look down the top of the die and see it work to get an idea of how much collet squeeze you're getting.
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