E-Tips now sporting a cannelure?

[Guest]

Picked up a couple of boxes of E-Tips yesterday at the BassPro in Nashville, TN. The 130gr .277cal are visually identical to the older batch I had. I will drop back and work up for sure, but no surprises there. Then I cracked open the box of 180gr .308cal E-Tips and discovered they all look like this:

Now, I know we had a discussion a while back about whether or not grooves were being added to the E-Tip (viewtopic.php?f=4&t=23509&start=0&hilit=E+tip+grooves) but the consensus then was that nobody except Super-7 had heard such rumors. So what's the story here? Can anyone from Nosler provide some insight?

For reference, I checked the part number, and it's the only 180gr .308cal E-Tip part number available, matching that on my old lot and on nosler.com. Hmmm...

 

[truck driver]

Can't make out the grooves in the pic Dubyam unless you mean the cannular, but that's a nice cockle burr on the shelf.

 

[kraky1]

I just picked up some 150/308's from SPS that have the same groove. I've played alot with light for caliber barnes ttsx's and see that they have a profile commonality that seems to ring a bell here. Basically those barnes bullets go to just under caliber width and then into a groove. In other words the width of a 308 barnes bullet just before the groove is probably .305 or .306. The heavier barnes bullets don't necessarily do this but the light ones do in several calibers and they are extremely accurate. Is it possible that barnes is letting the bullet sort of center itself and burn off a little pressure curve upon hitting the lands by doing this.
Now....I looked at the etips closely the other night. They go to caliber width just before the groove but just for a tiny tiny fraction of an inch. It would seem to me the same principal might apply here. Get the bullet centered and started....give it some relief and then the serious bearing area comes into play. On the 150 etip with the band where it is and the boattail there isn't a real lot of bearing area gonna be working on that long sucker.
Maybe I'm goofy but in my bud light drinking mind it makes sense to me.

 

[kraky1]

Oh....and according to my bullet comparator the new ones are .030" different from the base of the bullet to the ogive even though the oal of the bullet is the same...this in comparison to some of the very very first etips out on the market.
Kinda thinking there is some fine tuning been going on here.

 

[JD338]

Are these bullets seconds? I am thinking that they have the grove for one of the ammunition manufactures.

JD338

 

[Guest]

They are firsts, in a sealed box, Jim. It's really thrown me a curve, for sure. I'm going to call Nosler tomorrow and see what they can tell me. If they're seconds or overruns that got in a "firsts" box, I'm going to suggest they have a bit better QC on that - and I'm not going to be pleased if I have to totally rework my 300Wby load. I just got it ironed out for this past deer season.

 

[kraky]

Mine were blems....just measured the groove and its .060". More than you see with a normal cannelure. I took a bullet and put it in the jaws of my caliper and looked at the contact points by holding it in front of a well lighted background. It just barely touches ahead of the groove. Maybe its all a coincidence but if it is I think it will have a good effect for the reasons above.

 

[DrMike]

I'll be most interested to see what Nosler tells you, dubyam. I'm with Jim in thinking these were built for a manufacturer and sent to you by mistake.

 

[bullet]

interesting indeed, can't wait to hear

 

[Guest]

I'll certainly post what I'm told. I bought these at the BassProShops store in Nashville, TN, just this Tuesday afternoon, between client meetings while I was up there for the day. The box was a new-style box (the very newest, slip-top style) as opposed to the 130gr .277cal which were in the "sleeve style" box. I don't think this was an accidental mishap, but I'll see. If they've gone to grooving these at the ogive, I'll be curious what that does to my preferred loads.

 

[bullet]

I am inclined to believe it is their newer tweaked version, but we will see.

 

[JD338]

WM

Talk to Mike Harris or Mason Payer

JD338

 

[SJB358]

Pretty interesting Dub. I'm betting its a new tweak on the bullet though.

 

[DrMike]

Pretty interesting Dub. I'm betting its a new tweak on the bullet though.

You're on. What say, coffee next time you're in town?

 

[bullet]

Pretty interesting Dub. I'm betting its a new tweak on the bullet though.

You're on. What say, coffee next time you're in town?

Hey I am with SJB358 and you're on (of course if we are wrong getting up your way to by you that cup of coffee might be tough) :mrgreen:

 

[SJB358]

Pretty interesting Dub. I'm betting its a new tweak on the bullet though.

You're on. What say, coffee next time you're in town?

Heck yeah Mike. Matter of fact, coffees on me either way!

 

[Guest]

I guess since I'm the one making the call, I can't get in on any of this action, huh? Shucks. I'd like some Canadian coffee. I could make a trip up in the fall and maybe stumble into an opportunity to hunt while I was there...

 

[Guest]

Okay, guys, just got off the phone with Mason. He's a nice fellow, by the way. Here's what he told me:

The groove is on these bullets for two reasons. First, it enhances accuracy. Second, it can be used as a crimping groove. The groove will be on all E-Tips, but placement will be bullet specific, based on Nosler's testing. I asked if the BC would be affected, and Mason said it was miniscule and should not affect drops.

So this is a new development for all E-Tips. I suspect the groove serves the purpose of reducing the start pressure slightly, and aligning the bullet with the rifling more concentrically. A quick measurement with calipers shows the leading edge of the groove to be .307", as best I can measure, which is consistent with the nominal bullet diameter of the shank portion of this same batch of E-Tips. The ogive begins immediately ahead of the groove, but enough so that there is a measurable area of nominal diameter ahead of the groove. It may still serve to better align the bullet in the bore, but I am not able to conclusively say that.

As a side note, these are, on cursory examination, pretty consistent. I took out 5 bullets (from a box of 50, that's 10%) and measured and weighed them. For a 10% sample, nominal diameter was .307" across all bullets. That's a caliper measurement, so not entirely perfect, but it's consistent enough to satisfy me. I'm not going to go to the trouble of mic'ing these things. Weight showed slight variability, from 179.7-179.9gr, but again, I'm not going to quibble over .2gr of bullet weight. I also compared ogive profile for these, and best I can tell, they're identical in form, other than the groove. I did no more than compare them at multiple angles, using direct and indirect light. But side-by-side, they're carbon copies of one another except the groove.

I'll try to work up a load for these this spring and post my results, compared with what I was getting from the original E-Tips.

 

[bullet]

Dub, now I got to try them

Dr Mike, I don't know about scotty, but I am going to try and find a way to come for that cup of coffee. :mrgreen: :mrgreen: I need an excuse to come see you and hunt. :lol:

 

[truck driver]

Thanks For the follow up Dubyam. Now for the coffee when it stops snowing in Canada.