6.5 Grendel - Shoulders collapsing with Gold Dots

[SquarePizza]

I have been shooting 120 SMKs out of my 6.5 Grendel for awhile now, but I wanted to work up a load with 120 Gold Dots to use as a deer round. The gold dots have a very similar profile as the SMKs, but their jackets are super dark and rough looking.

The first few loaded fine, but acted like the copper jacket had a lot of drag on it going into the necks. After the first few, I started to get collapsing shoulders where the shoulder would roll back into the body of the case. I checked the diameter of the ball and they are coming out at .264 but they seat so much harder than the sierras and I just can't figure out why they are destroying cases. And since I'm using Lapua brass, I am none to happy losing brass.

 

[mcfred]

Anneal the necks, verify the ID chamfer so it does not push up a burr when seating bullets, use some dry film lube (molly, HBN etc.) and check the neck tension. If your sized necks have more than .003" neck tension then you may need a larger expander ball or a die that does not crush the neck as small.

Are you wet tumbling with SS pins?

Also, when you mic the projectiles, SMK v GD, are they the same diameter?

 

[spife7980]

Yep, what Mcfred said.
Make sure the cases have a good chamfer in them. The gold dot has a shorter boat tail so it’s much more wedging itself in the neck instead of going in smoothly and gracefully like the match kings gentler transition.

Is the lapua brass the same fired from before or new? Because new lapua has a hell of a lot of tension, opening the necks up could be a huge help.

If you said the diameter of the ball then they are coming out .264. The ball measures .264 or the cases inside diameter does? I ask because both of those would be wrong. The ball should be around .262 and the cases inside diameter should as well but inside diameter is tough to measure. Measure the outside diameter of the cases sized (or new, whichever) and then the diameter loaded to see how much interference fit there really is.

Did you try a matchking at that same time to make sure that they were seating as normal to narrow it down to just the speed bullet?

 

[SquarePizza]

Virgin lapua brass with factory annealed necks. Ran them through the sizing die before loading. I loaded 15 SMKs and the intent was to load 5 GDs at the same time. SMKs slide in like they should, though I never measured their diameter.

The .264 measurement is from the OD of the gold dots, taken by running the calipers down the ball and measuring the widest spot. I forgot to check the ID of the cases, I will size some more later today and check.

 

[spife7980]

You had an expander installed in the sizing die? Just have to ask the obvious at the start. If so then they should be fine. With the over ample tension from the factory you should have felt it expanding as you inserted the case into the die over the expander ball and as they were extracted as well.

Sounds like you need to add a chamfer to the cases. When I just load lapua Im always shaving bullets because they have a sharp angle instead of a gentle chamfered ramp. Can you see any copper built up around the top of the loaded necks like in the blue arrows case?

 

[SquarePizza]

Yeah I can feel the expander ball. I am using a redding FL resizing die and seater.

The odd part is that there is no shaved copper jacket which I would have expected with the added resistance. The SMKs are flawless when seated. I barely feel them going in and they shoot amazing. I just wanted a hunting bullet to have on hand.

I am going to pull the wrecked brass apart today and see if I can salvage any of it, that should give me a better look at the the GDs to see if they had any damage going in.

I think I might order some cheap brass if I am going to be playing around with hunting rounds.

 

[spife7980]

I was doing a comparison on 270 bullets and I noticed a similar thing, the brass had 3-4 thous of tension instead of the preferred 2.
The berger classic hunters have a super long smooth boat tail and they slid in like butter.
The gameking was a bit shorter and steeper and had more resistance to seating but were still very easy and smooth.
The nosler ballistic tip with its short boat tail gave a bunch of resistance and were just ever so slightly larger in diameter when I put it on the micrometer. If I were to load the ballistic tip I would have gotten an expander another thou larger.

In comparing those the speer might as well be a boot next to the mathcking. Not very graceful looking. I bet if you micrometer them they will be ever so slightly larger as well.

vs

Give it a good chamfer and the dry imperial lube will certainly help.

 

[Sigguy229]

I have been shooting 120 SMKs out of my 6.5 Grendel for awhile now, but I wanted to work up a load with 120 Gold Dots to use as a deer round. The gold dots have a very similar profile as the SMKs, but their jackets are super dark and rough looking.

The first few loaded fine, but acted like the copper jacket had a lot of drag on it going into the necks. After the first few, I started to get collapsing shoulders where the shoulder would roll back into the body of the case. I checked the diameter of the ball and they are coming out at .264 but they seat so much harder than the sierras and I just can't figure out why they are destroying cases. And since I'm using Lapua brass, I am none to happy losing brass.

I'm having the exact same issues with 120 gold dots for Grendel and 115 gold dots for 6.8 SPC. No issues with Barnes TTSX. Must be the bullets. Much higher force is needed to seat those bullets.

 

[Middle Man]

The Gold Dot Rifle bullets aren’t traditionally jacketed. The copper “jacket” is electro plated on the bonded lead core (same as Federal Fusion). That’s the root of why they aren’t as ”smooth” as SMK jackets.

The Gold Dot Blackout bullets I loaded shaved bits of copper here and there (not much boattail either), but never crushed any cases. Chamfer the case mouth...

 

[Sigguy229]

Thanks for the reply