crimping

I'm using Federal fusion brass, only fired once with factory load. with Win primers.

I had a feeling it was a resizing problem. or related to it somehow. I'll start to check the diameter of the neck from now on and see if it only does it to certain sizes.

and for now i'll just redo the cartridge just to be safe.
 
its for my 6.5 x55 140 gr Sierras.
Its fine after the reszing seating combo, it only happens after I crimp the cartridge. So I'll either put a tiny little crimp on her from now on or only if the bullet has cannelure
 
its for my 6.5 x55 140 gr Sierras.
Its fine after the reszing seating combo, it only happens after I crimp the cartridge. So I'll either put a tiny little crimp on her from now on or only if the bullet has cannelure

Yeah, I think this is a prudent course of action based on what you've shared with us.

No cannelure, no crimp is my mantra typically.

-M
 
So I'll either put a tiny little crimp on her from now on or only if the bullet has cannelure

Obviously the whole crimping thing is not working out for you.....If you insist on it try to pick up some Hornady interlocks as they will consistently have the cannulure that you need.

Ive never had to crimp for any cartridge that I load.....If crimping was that important you wouldnt' see so many bullets with no Cannulure. I know there are some exceptions for some chamberings / rifles / handguns....6.5x55 is not one of them. Another thing is that if you crimp you have to trim your brass and with good consistency (lenght).
 
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I shoot a Savage .223 and was trying to develop a load that was decent for 55 grain FMJs. I got the powder load and speed where i wanted it but the grouping was terrible. I bought a crimp set up and started crimping the 55 grain bullets. What a remarkable improvement. From Dinner plate at 100 yards to minute of gopher.

Also developed a load for the 62 grain FMJs and with the crimp, it was the same scenario, Guess the crimping allows more pressure and creates better accuracy. you can crimp any bullet...cannalure or not.
 
Based on the LEE book, crimping only adds around 200psi. In other words, almost non-existent.
It isn't that the crimp really adds anything for pressure. It just helps to make them uniform. Bullets reloaded for a particular rifle, using standard components are usually loaded to a COL with the bullet just touching the lands of the rifling. This eliminates "bullet jump". This also allows pressure to build up uniformly until the bullet leaves the case. When using shorter bullets like a 100 gr in a .30-06, then you need another method of standardizing the pressure build. That is where the factory crimp comes in. Now we all know that factory rounds are all crimped because "they don't know what type of firearm you will be shooting with" and they don't want any bullets pushed in by recoil. Okay. Fine. But that is what makes factory ammo so accurate and consistent. The Crimp. Standardizes the pressure build up which eliminates bullet jump. Basic physics. I crimp EVERYTHING.
 
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I missed what the OP was using for a crimp die, but if his bullets are securely held before he crimps, then it is not inconsistency in neck thickness nor bullet diameter. If he is crimping (normal roll crimp) a non-cannelured bullet, he may in fact be swaging the bullet diameter sufficiently that some bullets become loose. If he is crimping cannelured bullets, (in the cannelure!,) then I'm hooped for an explanation.

What a crimp, beyond holding the bullet in place in violent actions or recoil, is to hold the bullet against the early build up of pressure, so that the pressure curve is more uniform. (Variations in bullet diameter, case neck thickness, case neck inside diameter, seating depth, and on and on, are sort of overcome with a nice crimp. If you are using best quality components, following precise methods, using premium tools, the variations are pretty near eliminated. Crimping likely becomes the variable then!)
 
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