pretty new to reloading and I want to load some accurate .223/5.56 with 77gr Sierra SMK or TMK and was wondering how important having the cannelure on the bullet and crimping is. Will I lose accuracy by having a cannelure and crimping the bullets and if so is it enough of a difference that I'd even notice? I'd like to try and get sub MOA out of my loads but I don't need them to be 0.5moa or anything crazy like that and I'd rather have the crimp to keep bullets from getting pushed back into the case if it's not going to degrade accuracy significantly.
Cannelure and crimping
- Thread starter seamus
- Start date
Depends what you are shooting them out of. For a semi-auto I would recommend crimping for sure as you can get bullet set back as the shell is fed into the chamber rather vigorously.
For a bolt action, probably not necessary as the .223 is light recoiling and and you are unlikely to get bullet set back from the recoil.
Crimping does take a fine touch. Some is good, too much and you damage the bullet or collapse the neck in to the case when seating the bullet if too much crimp is set. Rounds won't feed and chamber properly then.
For a bolt action, probably not necessary as the .223 is light recoiling and and you are unlikely to get bullet set back from the recoil.
Crimping does take a fine touch. Some is good, too much and you damage the bullet or collapse the neck in to the case when seating the bullet if too much crimp is set. Rounds won't feed and chamber properly then.
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- Location
- Western Manitoba
I do not have too much experience at crimping jacketed bullets - I think the cannelure is to accept a "roll crimp" - Lee makes a Factory Crimp Die that does not appear to need a cannelure on a jacketed bullet at all. I found that for various rifles here - for the bullet "jump" that I want - might have the cannelure down inside the neck or way out in front of the case mouth - not sure "cannelure" is necessarily at best distance for all rifles and cartridges. If you are loading up a .223 Rem cartridge, those same bullets might be used by somebody else in a 22-250, or something else - if there is such a thing, I am not aware of a bullet sized specifically for your cartridge - or the cannelure placed on the bullet for your rifle's lands-to-bolt face distance.
Welcome to the "hunt" for a sub-MOA loading - might or might not have anything to do with what someone else does or does not do. Besides your load, your "group" is going to be a function of your rifle's bedding, the quality of that barrel, the barrel's twist rate and the length of the bullet that you use, the barrel's level of cleanliness or fouling, the condition of your muzzle, perhaps the ring mounts or the scope that is installed, and YOU, the shooter and your abilities - and there are likely other influences at play as well. Is not ONE magical thing that creates small groups - usually - everything has to come together at the same time. A saying from somewhere - "holes on target do not lie" - they will tell you if what you altered improved, made worse or was waste of your time - but you have to burn powder to know. To build up an accurate system - study up a bit on statistics - a single three shot group is not proof of about anything - some will say a group of five, or a single group of 10 shots is not much for "proof" either - I think it was US Army that would fire 4 x 10 shot groups to accept a batch of ammo or not.
Welcome to the "hunt" for a sub-MOA loading - might or might not have anything to do with what someone else does or does not do. Besides your load, your "group" is going to be a function of your rifle's bedding, the quality of that barrel, the barrel's twist rate and the length of the bullet that you use, the barrel's level of cleanliness or fouling, the condition of your muzzle, perhaps the ring mounts or the scope that is installed, and YOU, the shooter and your abilities - and there are likely other influences at play as well. Is not ONE magical thing that creates small groups - usually - everything has to come together at the same time. A saying from somewhere - "holes on target do not lie" - they will tell you if what you altered improved, made worse or was waste of your time - but you have to burn powder to know. To build up an accurate system - study up a bit on statistics - a single three shot group is not proof of about anything - some will say a group of five, or a single group of 10 shots is not much for "proof" either - I think it was US Army that would fire 4 x 10 shot groups to accept a batch of ammo or not.
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All my loading is done for competitive shooting in both .223 and .308. The rifles these rounds are going into are single shot bolt action rifles. I have never crimped a bullet into a case. Neck tension should be enough to hold the bullet in place even if you are shooting it through a mag fed semi auto.
I have crimped my Service Rifle match ammo - typically used 69 and 77SMKs or Hornady 68 and 75 HPBTs, none of which have the cannalure - for going on ~15 years.
I use the Lee Factory Crimp die just enough to give the bullet a light indent.
No issues with accuracy, degradation of uniform concentricity of the rounds, and it actually improved my SDs a bit as the neck tension was more uniform/repeatable with the consistency of the crimping procedure.
If you run ammo in a semi auto, eventually you will run into a fouled loading the potential for bullets being jammed back into the cases.
I did this too for my SR25, and 308 loads and compared the on-target results in my TRG22.
I would agree that if you are not planning to run it in a semi-auto, it is not necessary, but if you want that extra assurance that bullet isn't going anywhere (outside of once chambered), it is possible to maintain accuracy and crimp your rounds.
I'd recommend to run your own testing though as ymmv.
I use the Lee Factory Crimp die just enough to give the bullet a light indent.
No issues with accuracy, degradation of uniform concentricity of the rounds, and it actually improved my SDs a bit as the neck tension was more uniform/repeatable with the consistency of the crimping procedure.
If you run ammo in a semi auto, eventually you will run into a fouled loading the potential for bullets being jammed back into the cases.
I did this too for my SR25, and 308 loads and compared the on-target results in my TRG22.
I would agree that if you are not planning to run it in a semi-auto, it is not necessary, but if you want that extra assurance that bullet isn't going anywhere (outside of once chambered), it is possible to maintain accuracy and crimp your rounds.
I'd recommend to run your own testing though as ymmv.
Pistol rounds I crimp. Only rifle rounds I crimp are tube fed and my Garands. I was getting first shot flyer and searched the internet and found that crimping helped it. Now the first shot stays in the group instead of 3 or 4”‘S away.
I suggest you start with no crimp, as you search for accuracy. Once you have the best load, you can try crimping to see if it helps - or hurts.
I have shot thousands of rounds of 223 in an AR and have never crimped.
I have shot thousands of rounds of 223 in an AR and have never crimped.
Thanks for all the info, I wasn’t aware that you could put a light crimp on non-cannelured bullets. I have a raven with a criterion barrel and I want to try and get the best accuracy I can out of it and learn how to shoot to a bit further ranges. Because it’s a semi I was concerned about bullets potentially getting pushed back into the case.
This could have been written by myself, geez. I agree completely aside from whatever he meant by "fouled loading"? I definitely suggest finding this sort of thing out for yourself but I can't think of an instance where the crimp degraded accuracy, my experience was much more the opposite or at worst, no measurable effect. Even in relatively violent actions like the M1A it is very doubtful your bullet will move.
"fouled loading"
In my mind equals any round that doesn't load into the chamber smoothly - whether it misses the ramps and nose dives and headers straight into the barrel extension for whatever reason or maybe its a hard extraction on spent casing and a fresh round heads right into the back of the spent casing still in the chamber - or anything in between. It's a 'be all' for FTFeed or FTEject/ Extract that affects your ammo - maybe it pushes the bullet into the cartridge (bullet set back), or it jams the cannelure to one side or maybe it is the bolt running over a round and gouging the side of the brass slightly.
It is nice to have ammunition that can deal with some of that 'hard use', and not worry about bullet set back - especially if you're on the clock and want to get all your rounds on target during a timed course of fire.
In my mind equals any round that doesn't load into the chamber smoothly - whether it misses the ramps and nose dives and headers straight into the barrel extension for whatever reason or maybe its a hard extraction on spent casing and a fresh round heads right into the back of the spent casing still in the chamber - or anything in between. It's a 'be all' for FTFeed or FTEject/ Extract that affects your ammo - maybe it pushes the bullet into the cartridge (bullet set back), or it jams the cannelure to one side or maybe it is the bolt running over a round and gouging the side of the brass slightly.
It is nice to have ammunition that can deal with some of that 'hard use', and not worry about bullet set back - especially if you're on the clock and want to get all your rounds on target during a timed course of fire.
