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Posted: 4/25/2009 7:30:47 PM EDT
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I'm setting up to do my first .223 reloads and I'm currently setting up my seating die. I can't find any data that gives my specific bullet, Hornady 55gr FMJBT, but I did find this http://accurateshooter.net/Downloads/sierra223ar.pdf it calls for a COL of 2.250", problem is I'm not even on the cannalure of the bullet. I have a Speer book that has a 55 gr FMJ that calls for 2.215" which should do the trick but they used a CCI magnum primer for the load data and I'm using Rem 7 1/2's. My Lyman book is a useless paper weight, it only has one 55gr and it's a soft point non boat tail. Any info or advice would be great. TIA
PS the cases have been sized and check out ok on my case gauge. |
| According to the Sierra reloading guide, the cartage OAL should be 2.26". This can be different depending on your mags, because that is the most important thing when you are loading for any semi-auto firearm. I load for my mags (C-product and USGI) 2.265-2.270". I leave the .005 to play with because most 55gr bullets are slightly different lengths. |
| I just found this http://www.brianenos.com/forums/index.php?showtopic=49042&hl=Exodus . |
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Quoted:
If you set it farther back, there will just be more "jump" from the receiver into the barrel. The more jump you have, the faster the throat erodes. Good point. I wonder if there's a poor mans way of measuring the optimum "Jump" in a particular rifle. BTW is the distance your talking about the headspace? Thanks |
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I just measured some XM193 that I have and it comes out to 2.250" OAL. Reading that other forum, it seems that based on how Hornaday designed their bullet, it must be set back a little farther.
As far as jump and headspace goes, headspace refers more to certain dimensions of the case. I'm not too up on that, but I think in .223, it is the bottom of the case to the top of the shoulder. If this is too long, the case might not allow the bolt to close completely and result in blowing the side or top of the rifle apart. I don't know what to tell you about measuring the best jump, other than try a few different OALs shooting from a stable position and keep track of the changes in group sizes. |
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Seat the bullet to the cannelure if you're going to crimp.
Otherwise, seat the bullet at least one diameter in to the case, unless that yields a length longer than 2.26 inches. The general rule of thumb is that the bullet should be seated one to one-and-a-half diameters in to the case. 2.20 to 2.25 inches, or lengths in between, whatever works for you. The cannelure is provided if the loader wants to use it for a crimp. Crimps are optional, and there is nothing sacred about seating to the cannelure. Forget all that business about jump to the lands above. For starters, you're stuck with it in most (probably all) off the rack AR barrels. Second, throat erosion is caused by the amount of burning gun powder torching out of the case. More powder, more erosion and shorter barrel life. Your rifle will likely be shootable for 5000 rounds or more, depending on your accuracy demands for the gun. One other factor about the long throats in off the rack guns; they're so long that you might not be able to touch them even with 80 grain bullets. My Colt rifle is throated so long that the bullet (75 grain AMAX's or 80 grain MK's or Bergers) falls out of the case before touching. A short light weight bullet will never get close. Don't worry about it, the rifle will shoot fine. Jump to the lands is one factor in pressure production. A long throat is a dodge used to mitigate the high pressure of some rounds. It also guards the rifle manufacturer against careless reloaders that don't trim long cases. However, that comment does not mean I advocate anything but case trimming to lengths less than the SAAMI maximum number (1.76 inches for .223 Remington). |
| I have been loading my IMI 55gr fmj to a 2.250" OAL. According to my data, I used this length with winchester as well. After reading this post, I had to run downstairs and do some measuring with my calipers. My 55gr IMI fmj's were approx. 0.745" long––I am out of winchester. My hornady 55gr. fmj's are approx. 0.733" long. I just received the Hornady bullets a month ago.I haven't loaded a hornady bullets yet. From the base of the bullet to the cannelure appears to be the same length for both bullets––I forgot those numbers running up the stairs. So, In this case, Hornady's cannelure is not further forward. The bullet is a little shorter. Different manufactures make bullets different. I have read the sierra data. I have no experience with their 55 gr. fmj. Like with any new component or change in length, start low and work up to a load that works for you in your rifles. It would appear if I loaded to the cannelure, the Hornady cartridge would have a shorter length. There are many things that can mess with pressure and velocity. If you want to load to the cannelure and crimp, make some test rounds. Crimp/no crimp, it's up to you. I think everyone has some good information here. |
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You didn't mention the powder you are using, however,
Hodgdon's site lists 2.200" COL for all the 55gr bullets (including hornady). |
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Simplified answers follow:
Quoted:
I'm setting up to do my first .223 reloads and I'm currently setting up my seating die. I can't find any data that gives my specific bullet, Hornady 55gr FMJBT, but I did find this http://accurateshooter.net/Downloads/sierra223ar.pdf it calls for a COL of 2.250", problem is I'm not even on the cannalure of the bullet. Seat the bullet where YOU want, not where the cannelure is. If you crimp, it is entirely reasonable to seat to a length that allows you to crimp into the cannelure but it is not necessary. OAL's of 2.250" are MAX. Anything shorter will fit in the magazine. Longer will not, and will have to be single round loaded. I have a Speer book that has a 55 gr FMJ that calls for 2.215" which should do the trick but they used a CCI magnum primer for the load data and I'm using Rem 7 1/2's. The 2.215" is also fine because it is less than the 2.250" MAX. Primer choice is a guideline. You must ensure your primer choice works. Recipes are not hard and fast. My Lyman book is a useless paper weight, it only has one 55gr and it's a soft point non boat tail. IMO, Sierra makes the best reloading guide on the market. I have nothing by LYMAN. Any info or advice would be great. TIA PS the cases have been sized and check out ok on my case gauge. Case gages are better than nothing but not by much. Get yourself a Hornady Head & Shoulders gage, Bullet Comparator and a Chamber All gage set. You can thank me later. |
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For a beginner.............I say crimp it in the cannelure if your bullet has one.
It's good practice for getting to know your equipment. And it should be the "correct COAL" for that bullet in most circumstances. Remember, the crimp or COAL is not written in stone. What you see in a re-loading manual is a sort of guide. YOU decide your level of SAFETY and you're free to experiment. ________________________________ I assume........... The bullet mfn has a testing facility. And, that they have tested and made assumptions about the bullets that they are producing and what it'll be used for. So, for a .224 dia. 55 gr. FMJ bullet...........the mfn will probably assume that your cases are properly trimmed and that the bullet will be shot out of an AR15 (mimic of/or close to, M193). So, they'll put the cannelure where it'll be SAFE. Because, they'll assume that you'll crimp it in the cannelure. The cannelure is there (assuming you will crimp it there) for those that want the "extra protection" from bullet set back. ________________________________ Another assumption..........have you noticed that most Match bullets does NOT have a cannelure? Why do you suppose that is the case? A cannelure adds to the cost. A cannelure "deforms" the bullet. But........the military specs a cannelure. Because, in their opinion, it's worth it. Any round that would "telescope" into a cartridge case, could/will lead to a "bad day" for our troops. _________________________________ For us civilians.........YOU don't have to crimp it in the cannelure. IT'S NOT WRITTEN IN STONE. For some, the cannelure is convenient and for some it's ignored. Aloha, Mark |
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