Thread: Remington 700 Sako and M16 extractor conversions

Originally Posted by Spanners

As a tool for 'stopping at XXXpsi' or 'this load is XXXpsi' its useless as there is no reference or calibration - thus the issue

How can you quote a number or advise someone that their load is too hot??
Thats exactly whats been going on.. "the Oehler said this, and your load is dangerous"

This discussion has been going on for 10 YEARS on Accurate Reloading, as has the 'add powder till you get book velocity' being total bollox

What's your methods spanners? Would be nice to know.:rolleyes:

It's easy to tell if someones loads are hot when they are faster than they should be etc. An if the pressure testing way that in accurate why do they still make it? An all books quote them an Lapua spec there brass?

sent from my Samsung s3 using tapatalk 2

My method is to work to a speed I'm happy with and with brass and primer signs that I'm also happy with.
Not to say it's the right way or final way but I've never popped a primer or case.
How many people have popped a primer? I bet it's alot. That's way past pressure limits.
long term users with pressure gear pop them.

Oehlur even tells people to put M43 after numbers they quote as they arnt an exact pressure they are a pressure obtained on a M43 and nothing more.

The point is, that without a calibration reference the numbers are basically useless and given there is no way to calibrate...

What it can be useful for is testing different powders. Area under the curve and velocity depicts efficiency. If the indicated peak is lower and area larger for same speed, then you'rw onto a winner. However the peak number is nothing more than a reference for the next shot to see if it's more or less.
It can also show some interesting things like 2ndary burn- something that even the big boys say doesn't happen.

What are the brass and primer signs you adhere to Spanners?

This discussion isnt about my practices, (as I stated above, Not to say it's the right way or final way, and quite frankly, couldnt care less what someone thought of the way I do my own things ) its about the accuracy or inaccuracy of strain gauge gear

Originally Posted by Spanners

This discussion isnt about my practices, (as I stated above, Not to say it's the right way or final way, and quite frankly, couldnt care less what someone thought of the way I do my own things ) its about the accuracy or inaccuracy of strain gauge gear

No its not.......its about extractors........................................ ...

still dont see why they would make somthing if the 'fudge' factor is ment to be as big as you say. how do the reloading books get theres? they all fudged to?

must be time to go back to buying ammo

Originally Posted by Spanners

This discussion isnt about my practices, (as I stated above, Not to say it's the right way or final way, and quite frankly, couldnt care less what someone thought of the way I do my own things ) its about the accuracy or inaccuracy of strain gauge gear

GD called you out on yours and others systems and why they're better, please explain if you can.

Originally Posted by Mike H

GD called you out on yours and others systems and why they're better, please explain if you can.

Where did he call him out?
-Have been following this thread with interest, but I must have missed it??

Originally Posted by Greg Duley

Sorry, been away hunting for a few days.
Well, we've used the Oehler ballistic laboratory extensively for a number of years now, across a wide range of calibres, both factory and wildcat. We are using it on barrels with a straight cylinder chamber section so the wall thickness can be measured precisely. We have found the results both consistent, common sense and matching reliable sources we trust. We have never seen an anomaly that leads us to believe the system doesn't work, so long as you are meticulous with the inputs.
Please do tell us what system you think is better for our purposes?

Last sentence

Originally Posted by Mike H

Last sentence

Ah, I see.
-I think the point Greg is making is: That currently there isn't a better system than the strain gauge available.
-I think the point Spanners is making is: That it is an imperfect system.

-I think they are both right.

And I'm trying to find out what Spanners does that makes his system so reliable. I'd trust the Oehler used by the right person ahead of primers or brass signs on their own.

We certainly are a long way away from extractors and the original intent of this thread which as it appears to me is an attempt by Greg to protect his business from a perceived threat or challenge from other Greg (or maybe just some free advertising for his gunsmithing services).

Perhaps we should get back on topic by asking the interested parties to back up their extractor statements with ohhhhh say some EVIDENCE for their claims - The bolt is undergoing triaxial stress at multiple locations while under hydrostatic tension - a situation which is difficult to model on the back of a fag packet. the obvious engineers answer would be finite element analysis of the parts in question to give us some concrete numbers and enable us to make an informed choice as to who to believe. In the absence of this or similar evidence I can only assume they are both simply playing a guessing game and potentially playing with the lives of their customers (think exploding dan cans).

So go on then gents - exactly what process did you follow to decide how to modify another manufacturers product to operate safely outside its design specifications?

Fair call cyclist. I guess we're waiting on KG then as GD put his thoughts up in the first post.

Originally Posted by Cyclist

We certainly are a long way away from extractors and the original intent of this thread which as it appears to me is an attempt by Greg to protect his business from a perceived threat or challenge from other Greg (or maybe just some free advertising for his gunsmithing services).

Perhaps we should get back on topic by asking the interested parties to back up their extractor statements with ohhhhh say some EVIDENCE for their claims - The bolt is undergoing triaxial stress at multiple locations while under hydrostatic tension - a situation which is difficult to model on the back of a fag packet. the obvious engineers answer would be finite element analysis of the parts in question to give us some concrete numbers and enable us to make an informed choice as to who to believe. In the absence of this or similar evidence I can only assume they are both simply playing a guessing game and potentially playing with the lives of their customers (think exploding dan cans).

So go on then gents - exactly what process did you follow to decide how to modify another manufacturers product to operate safely outside its design specifications?

Both Gregs are paying advertisers . As far as Im aware no one has been injured by a Dan can let alone killed.
But really I gotta ask, how do you get up and out of the house in the morning?

Tui - from post approx #7 onwards this and been about pressure - at least on my screen
Fudge factors #1- from 'Dr' Oehlers own mouth "...suggest using 7K psi offset for chrome-moly barrels and 5K psi offset for stainless barrels.."
Stainless steel depending on its makeup can range from 400-750 MPa - Chromoly around 500-800 MPa (from memory) ..4130 as an eg prob has around 20% variation as its own grade.
Please explain to me how you can put the gear on a rifle, fire a shot and say ' that round was 70k psi'???

Mike - you obviously dont read the whole post or its not being absorbed, twice now.. "...Not to say it's the right way or final way.."
I've never said its better or worse than anything, it has however been the basis of ammunition development for over 100 yrs.

What I have said a number of times, is a system that has no way of calibrating it is nye on useless for quoting pressure numbers - its a pretty simple fact, and if you disagree, then provide evidence to the contrary, rather than trying to turn the discussion around.

I've also pointed it where it can be used for gain.

Dont get me wrong, I'd buy one in a heartbeat if it come with a possible way of being calibrated.. 10+ yrs later, there isnt one..

So how is your method able to be calibrated Spanners? Thats all I'm trying to work out. Using brass and primer signs? In what way?