Min seating depth

Koda

Koda

Hammer Time Executive member
280AI, 140g Absolute Hammer.

I've got plenty of room in both the mag and reaching the lands.

Ive read from Hammer that you should have at least 2 PDR drive bands of neck contact.

Just to clarify, is the last ridge at the boat tail a drive band?

If the last ridge counts then that looks awfully weak to me (bullet on the right). Which of the two depths would you pick from the picture below?

1682128966470.png
 
Seat deepest to start. Seat to the last groove (from bottom?)

Why is it the advice here is opposite what Hammer suggest?
(start .02" off)
 
First or second band showing is preferable (better?). If you Have to (rare) you can go out further, but Steve suggests at least two bands to try to hold the bullet in the neck "minimum"
 
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Koda said:
Seat deepest to start. Seat to the last groove (from bottom?)

Why is it the advice here is opposite what Hammer suggest?
(start .02" off)
Click to expand...
You'll never get .02" off the lands with an Absolute, as the first part of that bullet to touch the lands is the top ring. It used to be an old rule of thumb to have at least the same length of bullet seated as the cartridge diameter to help with bullet to case grip and alignment, although with some short necks like on a 300WM, I don't think that is attainable. I try to have as many rings as possible gripping the neck with Hammers, and that usually means crimping in the top groove.
 
joevh said:
You'll never get .02" off the lands with an Absolute, as the first part of that bullet to touch the lands is the top ring.
Click to expand...
That's true, im aware of this so to clarify I was just wanting to start as close to the lands as practical for best velocity and lower pressure.

I wound up choosing the second valley, +1/8t crimp.

I did check 2 bands depth and while it felt solid by finger tips im just not yet confident 2 bands is enough grip especially for a hunting bullet carried in the field.
 
gltaylor said:
First or second band showing is preferable (better?). If you Have to (rare) you can go out further, but Steve suggests at least two bands to try to hold the bullet in the neck "minimum"
Click to expand...
I like the "bands showing" language.

@Koda - I must have missed the memo on the seating close to lands with Hammers. I've always been of the "Hammers love jump" supporter. All m Hammers are no bands showing, seated deep, except for the 234AI that I have one band showing. With no bands showing it was .8 MOAs. With one band showing I'm into bugholes. However, there is still a .060 jump for bughole groups.
 
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BFD 2.0 said:
I like the "bands showing" language.

@Koda - I must have missed the memo on the seating close to lands with Hammers. I've always been of the "Hammers love jump" supporter. All m Hammers are no bands showing, seated deep, except for the 234AI that I have one band showing. With no bands showing it was .8 MOAs. With one band showing I'm into bugholes. However, there is still a .060 jump for bughole groups.
Click to expand...
I cant recall where ive read it, there are a few "stickies" where Hammer (Steve?) Shares loading advice and somewhere I read to start .02" off.

Ive also always read Hammers are not sensitive to jump. I have not read they "like" to jump until now so i dunno what to think. Im new to Hammers so i havnt played with seating depth to control groups. Havent needed to.... So far in my limited experience Hammers all grouped the same in pressure ladders and when i found the safe velocity I wanted I just simply zeroed that charge and was done.
 
Koda, if I am reading this right(if) your question about. 020 off the lands is in reference to Steve's original post on loading hammer bullets dated 2/29/20?
This preceeded the absolute hammers line of bullets.
This was also prior to a bunch of testing alot of us have done with crimping.
Shinbone also posted a thread on groups with varying degrees of crimp. 1/8, 1/4, 1/2 that shows how grouping shows improving and degrading of group size with varying crimp pressures.
I'll link if I have a minute left in my day😛 busy farming. Good luck Alan
 
I've only got one load that prefers
.020 or any less. All my other loads jump from 20 - 160 thousandths (for reference). All but a very few of my loads are also crimped to varying amounts.
 
Koda said:
I cant recall where ive read it, there are a few "stickies" where Hammer (Steve?) Shares loading advice and somewhere I read to start .02" off.

Ive also always read Hammers are not sensitive to jump. I have not read they "like" to jump until now so i dunno what to think. Im new to Hammers so i havnt played with seating depth to control groups. Havent needed to.... So far in my limited experience Hammers all grouped the same in pressure ladders and when i found the safe velocity I wanted I just simply zeroed that charge and was done.
Click to expand...
Load develop batches with no bands showing, then one band showing. I bet you will find your spot.
 
Or they can look like "Grandpas" .270 Win. 156HH Two PDR's, 1/8 crimp. I kind of look at this no different than any other bullet to some degree. Start with max magazine COAL that still works with jump to lands and go from there. The 156HH shot great at this COAL and associated CBTO so I just crimped there in groove. I also agree I feel more comfortable having at least 2 PDR's in case mouth. So far haven't had any reason to change that. Except for .243 shooting 55's and 70's. Stuffed them in case.
IMG_4233.jpeg
 
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I sounds like there are various ways everyone is using that all work, like any other bullet. Im new to reloading and hammers so Im just looking for my own foundation if it even just works for me.
I just got home from the range and did my first pressure ladder with new Peterson brass so I need to go over that data.

And Butterbean... what the heck is that overbore battleship cartridge? lol :p that looks like it should hit mach 3...
 
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