Help tightening up Hammer groups

[LongWalker]

Wow l, thank you sir! Those are great detailed instructions. My Lee crimp die will be here Friday and hopefully the weather holds and I can get to the range over the weekend.

 

[skipglo]

Did you neck size with a mandrel instead bro-tato?

Saved my question!!!!

 

[HuntingBronco]

I just went through this. Where are you seating them? Trying a jump .05 is where you can start or seat them to the last groove. Also have you pulled the expander ball out of your sizing die? These all helped my groups immensely.

No expander ball? What neck tension does that leave you with? (Assume a lot!) Clearly worked for you!

 

[AZ82New]

I bought the 131 hammers for my ackley and expected them to just bug hole based on what I have read. I'm in the same bought, I'm only getting groups that are an inch. Barnes gives me half inch groups.

I'm honestly not sure I'll keep fiddling with them. I'm sure they can be accurate but I'm not seeing it yet.

 

[LongWalker]

The Lee collet die has a decapping rod that the collet squeezes onto (probably a better way to explain that). I run it through new brass and in almost every case it expands the neck so less tension than Lapua or Peterson out of the box.

 

[Priley]

No expander ball? What neck tension does that leave you with? (Assume a lot!) Clearly worked for you!

With that much neck tension the pressure has to be through the roof!!

 

[milboltnut]

VV550 is too slow in my experience for 150 grain bullet. Better off with nothing slower than RL 15 and noting faster than 4895 for lighter bullets. The hammers are like the Barnes TSX/TTSX with the grooves prevent extra fouling, preventing more pressure. The original barnes didn't have the serations and copper fouling was an issue.

 

[LongWalker]

No pressure signs until I hit 3300 fps so velocity was very good IMHO. Even at that speed/pressure just had ejector swipes no sticky bolt.

 

[milboltnut]

what kind of accuracy are you getting and at what range?

 

[LongWalker]

Three 3 shot groups were from an inch to an inch and a quarter at 100. But as I mentioned in my first post the wind was blowing pretty good

 

[Recon$$]

No expander ball? What neck tension does that leave you with? (Assume a lot!) Clearly worked for you!

No idea, I just took butter beans advice there. I've never had a problem just doing a full length resize with my brass and finding 1/2 moa loads so I haven't gone down that road. Steve from hammer suggested that the initial primer pop could have been pushing the bullet into the lands before the powder was ignited hence why they suggest the jump. So combined with the extra tension it solved my problem. Sorry I don't have a more in the weeds explanation. I just do the simple things as consistently as I can.

 

[ButterBean]

With that much neck tension the pressure has to be through the roof!!

No its not through the roof , It's perfectly fine, SMH

 

[ButterBean]

The Lee collet die has a decapping rod that the collet squeezes onto (probably a better way to explain that). I run it through new brass and in almost every case it expands the neck so less tension than Lapua or Peterson out of the box.

You need to sand the mandrel down to .003-.004 neck interference

 

[ButterBean]

No expander ball? What neck tension does that leave you with? (Assume a lot!) Clearly worked for you!

.003-.004 Depending on which brand of die you have