I have also shot a lot of Hornady and Sierra match bullets with never having an issue. I think case neck tension is more important than whether there is a cannelured or not.
Definitely agree. I also believe that the effects of a cannelure on fragmentation / terminal performance are negligible and far less important than shot placement and a variety of other factors.
Now, I’m definitely not saying that a cannelure is undesirable…because I also don’t believe that a cannelure has a substantial negative impact on accuracy as some people do.
My main point is that the lack of a cannelure does not in and of itself preclude a cartridge from being a viable defensive load.
I’ve had a lot of people tell me I’m nuts for saying that…which is part of why I posed this question to the forum.
I’ve shot a fair amount of non-cannelured Hornady 75 grain-ers through my AR. Never had a problem with bullet setback when I used a roll crimp or the Lee Factory Crimp.
I had no issues with factory B.H. 68s in two 20" A2s (one was a Colt), but the same A2 chambers gave me serious setback, {Danger Will Robinson}, with 68 gr reloads as well as some recent dummy 77s tested (manually hard-chambered from a mag). RCBS taper crimping - with or without cannelure, heavy or light, does not appear to make any measurable difference.
No issues (zip) with 77 grain reloads and a moderate amount of B.H. Mk 262 in several rifles /w M4 feed ramps. I mostly load 77 SMKs with cann and a very light taper crimp, but have gone through some non-cannelured as well.
Both with and w/o cann shoot well at 700M in my SPR; with slightly better “perceived” accuracy going to the /w cann version . I have a target pic posted somewhere with a sub MOA group at 700M with the cannelured 77 gr reload.
I prefer the cannelure since I open the case mouth a few thou in my loading process (and close it with the taper crimp die). I “think” the cannelure gives less opportunity to damage the bullet on crimping, but I could be wrong.
Ive fired thousands of rounds of match type ammo and the only ammo that has ever had set back issues was 45 GR JHP rounds. The mouth was so big it just caught on the feed ramps.
Never an issue with anything else both in M4 ramps and A4.
I have fired many Hornady 75’s as well as Nosler and Sierra 77’s all without cannelure. I don’t like the Hornady due to accuracy issues but have never had a problem with set back on any of the ones mentioned.
When I load the 75 gr Hornady bullets there is so much Varget compressed there is no way the bullet is going to set back from impacting the feed ramp. A faster ball powder like H335 may leave some open space behind the bullet but something like Varget is a compressed load and set back is not happening.
I’ve never had any 75/77 grain bullets fly worth a shit. Factory or Handloads… I’m getting a competition seating die today or tomorrow and we’re going to try to get Hornady Match and AMAX to do something decent.
Ive not loaded any 75gr pills because i read all over the internet that the case mouth has a gap between the bullet and the case when seated to mag length. Is this a different bullet youre using, or is there something else to it that i am missing?
The 75gr AMAX is too long to load to magazine length, the 75gr OTM is fine. I found out about the AMAX bullets after I bought them, but also found they would fit fine if I cut off the plastic tips and shot them all off.
I load the OTM’s to 2.260 with 23.0gr TAC and CCI #41 primers.
That’s true, but if you want to run 2,700 fps (or even faster), you can’t get there with Varget. Easily done and with no pressure problems with TAC, in an 18" SPR.
I tried TAC with Hornady 75’s and 77 SMK’s and 77 Noslers. I attained the velocity I was looking for at around 2700 FPS but I could never get good accuracy with TAC. Best groups hovered around 3-4 moa. I get 1.5 with Varget but give up about 75 FPS in velocity.
It’s a shame really because TAC is so easy to work with compared to Varget but my rifle just doesn’t like it.
You’re right I am not close to 2,700fps especially out of my 16" barrel. I am more interested in accuracy when using the 75 gr bullets not so much in the absolute maximum velocity. Varget has been pretty good for accuracy, but I did have some TAC, H335 and BL-C2 and I think some RL15 that I have not yet tried with the 75 gr bullets.