17 H pressures

[wally bennett]

Been sorting out some cases 17A/H and 17H and noticed that the 17H cases had very flat primers if i saw primers that flat on my 17A/H i would take that as a pressure sign as well as the flat primers the cases are hard to re-size compared with other case i have re-sized/de-primed in my time i have loaded 22H, 222, 223, 243, and 17A/H. Is it me getting old and weak or has anybody else noticed this
Wally

[Daryl]

Flat primers is usually a bit of headspace, or high pressures- or maybe both. My AH's run nice speeds, with no flattening to speak of. I do get the CZ cratering, but never a pierced primer.

Should note that a slight headspace problem in a Hornet usually means early case head separations in just a couple or 3 loadings.

[wally bennett]

Originally Posted by Daryl

Flat primers is usually a bit of headspace, or high pressures- or maybe both. My AH's run nice speeds, with no flattening to speak of. I do get the CZ cratering, but never a pierced primer.

Should note that a slight headspace problem in a Hornet usually means early case head separations in just a couple or 3 loadings.

Got no problems with my 17a/h but i run it a lot slower than others 3,660ft/sec the flatened primers are from Henrys CZ so dont think i will be re-loading them
Wally

[Chickenthief]

Can we assume that they are loaded the same?

Case capacity should be roughly the same so no luck there.
Throat length ie. bullet into the lands on the 17H?
Primers the same?

Case stretching is only a problem at the first firing from there on they fit the chamber unless you FL size then to kingdom come each loading.

Primer flattening at lower pressures occurs when a to short case is slammed forward by the firing pin. Case walls grip the chamber, the primer backs out until it meets the bolt face. Lastly the case stretches until it catches up with the primer and then it is seated flush but flat.

At higher pressures and in cases that fit the chamber it is due to (way) high pressure that flows the brass in the primer so it fills out the "void" between it and the case.

If they are factory loads then they are sized to a bare minimum and Hornady are known for their thin rims. So that will make a case rattle until fired and flattened primers are not unknown.

But then all primers are not created equal you know.
Some deform much easier than others due to thinner/softer cups.

[wally bennett]

Originally Posted by Chickenthief

Can we assume that they are loaded the same?

Case capacity should be roughly the same so no luck there.
Throat length ie. bullet into the lands on the 17H?
Primers the same?

Case stretching is only a problem at the first firing from there on they fit the chamber unless you FL size then to kingdom come each loading.

Primer flattening at lower pressures occurs when a to short case is slammed forward by the firing pin. Case walls grip the chamber, the primer backs out until it meets the bolt face. Lastly the case stretches until it catches up with the primer and then it is seated flush but flat.

At higher pressures and in cases that fit the chamber it is due to (way) high pressure that flows the brass in the primer so it fills out the "void" between it and the case.

If they are factory loads then they are sized to a bare minimum and Hornady are known for their thin rims. So that will make a case rattle until fired and flattened primers are not unknown.

But then all primers are not created equal you know.
Some deform much easier than others due to thinner/softer cups.

Yes this is with faxtory loads only not wiyh re-loads.
Wally

[Chickenthief]

I'm no expert here, but i seem to remember that Hornady factory ammo are notoriuous for flattened primers that are crimped in.
So until you test your own realods then disregard reading primers as a sign og how things are.

[wally bennett]

Originally Posted by Chickenthief

I'm no expert here, but i seem to remember that Hornady factory ammo are notoriuous for flattened primers that are crimped in.
So until you test your own realods then disregard reading primers as a sign og how things are.

Wont be re-loading the 17H rounds Mate henry has plenty of factory rounds and been promised a good supply so whilst he has plenty he will use them.
Its touch and go whether he will keep the 17H he recons there is not enough extra performance over the 17HMR for the cost of ammo HMR £0.28 per bang and 17H £0.85 per bang
I have told him i will load for his 17H but he says he is not happy with re-loads
despite the fact he cant get enough of shooting my 17A/H.
Wally

[Chickenthief]

Aww man, the 17H will do at 200yds what the 17HMR does at the muzzle.

17HMR is a little more expencive here so i can reload 2 17H for the price of one 17HMR.

But a fool and his money are soon parted.

[wally bennett]

Originally Posted by Chickenthief

Aww man, the 17H will do at 200yds what the 17HMR does at the muzzle.

17HMR is a little more expencive here so i can reload 2 17H for the price of one 17HMR.

But a fool and his money are soon parted.

I know but its his choice.
Wally

[Jeremy(WI)]

Originally Posted by Chickenthief

I'm no expert here, but i seem to remember that Hornady factory ammo are notoriuous for flattened primers that are crimped in.
So until you test your own realods then disregard reading primers as a sign og how things are.

The crimped primers was Hornady's fix for their messed up primer pockets. The new brass and factory ammo I have has good primer pockets