77gr SMK's-Cannelure or no?

[D1gger]

I need to work up a load for my new AR. 1-8" twist, 18" WOA barrel. I've got less than 100 rounds on it, but it really seems likes Gorilla factory ammo, loaded with 77gr SMKs. I don't see a cannelure on the bullets, but they could be loaded deep.
Should I go with the cannelure bullets or not, or does it even make a difference? In looking at the AR only load data, no one mentions it.

 

[needham]

at this point its load what you can find, or have.

non cannelure is perfectly fine.

 

[LRShooter101]

If the bullets in your Gorilla Ammo have a cannelure you would see it. They are not going to load a bullet from the factory that deep in the case to a point where you would not see it.

Cannelure Pros:
- Provides a better grip for the case to keep the bullet from being setback
- While it is not always 100% proven, bullets with a cannelure can potentially fragment quicker in a soft target

Cannelure Cons:
- They can negatively impact the BC and consistency of the bullet

If long range accuracy is your #1 priority, skip the cannelure. Just make sure you have decent neck tension, and you have a good feed path to the chamber, to prevent the bullets from being setback while feeding.

 

[whatsupdoc]

If you feel the need to crimp you use the ones with the cannelure otherwise use the ones without the cannelure.
I personally do not crimp and have no issues with the bullets moving. I would suggest a minimum of .002 neck tension.

 

[D1gger]

Thanks for the replies. I don't plan on crimping.

 

[Mike_in_FL]

I need to work up a load for my new AR. 1-8" twist, 18" WOA barrel. I've got less than 100 rounds on it, but it really seems likes Gorilla factory ammo, loaded with 77gr SMKs. I don't see a cannelure on the bullets, but they could be loaded deep.
Should I go with the cannelure bullets or not, or does it even make a difference? In looking at the AR only load data, no one mentions it.

I've tried both and it never made a difference in accuracy to me. I don't crimp these at all either and quite frankly calling what's on the Sierra a "cannelure" is a stretch compared to other bullets.

 

[Changed]

I've tried both and it never made a difference in accuracy to me. I don't crimp these at all either and quite frankly calling what's on the Sierra a "cannelure" is a stretch compared to other bullets.

I had the exact same result when testing with and w/out.

I bought all the 77SMK's I could find when they went half off at my local store. Both of these five shot groups are with canelure. Neither were crimped.

 

[LRShooter101]

Be careful "Judging Accuracy" by just looking at groups fired at 100 yards!

You can have a group that looks good at 100 yards, but looks like junk at 500 yards (or beyond).

A small issue with bullet consistency or BC variation (both issue with cannelures) is not going to show significantly at 100 yards. However those things can start to exponentially impact the accuracy the farther that the bullet travels.

Anyone that shoots 1,000 yard F-Class or Benchrest will confirm that you just can't take what you are seeing at 100 yards and be guaranteed that it will look that good at much longer ranges.

Unless it is an issue with the bullets being crimped, or interacting with the neck, inconsistently I would not expect to see a major difference in accuracy between the two at 100 yards.