Hrndy OAL Gauge

browninghunter86 · April 5, 2012, 12:15 AM

Just got my OAL gauge and modified cases for it. Followed instructions and set up but ***HOW DO YOU KNOW WHEN YOU OGIVE TOUCHES THE LANDS?**** Is this when slight pressure on plunger and bullet stops? On my 308 with Hrndy 165 BTSP I am getting a reading of 2.249"(Ogive) 2.815". Also modified case headspace is 0.003" smaller than my fireformed brass so do I add that to my reading? Some people online are saying to add it to get most accurate reading

I am getting that same reading everytime with every bullet I try so I am assuming this is correct.

Any tips or tricks to this would be helpful

deepcore · April 5, 2012, 12:41 AM

I adjust my readings to account for the difference in headspace between the Hornady modified case and my fired case.

I myself use slight pressure. I previously pushed too hard and then having to push hard on the wooden towel to dislodge the bullet I could see the (rifling's) scratches down the side of the bullet.

browninghunter86 · April 5, 2012, 12:51 AM

so if modified case is .003" less then add that to my final reading and should be gtg? When I used wooden dowel to get bullet out it barely is in there and comes out with hardly any resistance

Jim243 · April 5, 2012, 01:51 AM

Browninghunter, when you said the headspace of the mod case was 0.003 shorter than your fired case, are you measuring from the shoulder or case mouth? Also do you use a collet die or full length die when you resize??

It never made, no ever mind for me since I want to know the Max OAL of the chamber with case and bullet and that is what the gauge is designed to do.

The neck size on the mod case, plays no part in the measurement.

Jim

F. Guffey · April 5, 2012, 03:18 AM

The difference between the two measurements, the fired case is formed and should represent the distance from the bolt face to the shoulder of the chamber, the same information is available to a reloader that can measure the length of the chamber without firing a case (to fire form). When determining ‘maximum overall length’ with a transfer or Hornady gage the bolt is removed (on bolt guns), meaning the answer is yes, head space is added to the maximum overall length. Again, I am not the fan of seating the bullet to the lands, I am the fan of the running start, I want my bullets to hit the lands with a jump.

The difference in price between a transfer and a Hornady gage is about $32.00 dollars plus $7.00 for the modified case, the transfer is free. For free, the reloader can use the transfer to adjust the seater die.

http://www.dillonprecision.com/conte...ll_Length_Gage

If the reloader uses a fire formed case when determining ‘maximum overall length’ the head space is included. That means the reloader will be required to neck size and drill and tap the primer pocket/flash hole to modify the case. And again, there is no guarantee the maximum overall length case will feed, some could require chambering one at a time.

F. Guffey

browninghunter86 · April 5, 2012, 06:57 AM

Jim243: using the Hornady Headspace bushing and I FL size to be a slightly less than slight crush fit in the chamber.

mrawesome22 · April 5, 2012, 10:22 AM

Quote:

***HOW DO YOU KNOW WHEN YOU OGIVE TOUCHES THE LANDS?****

http://thefiringline.com/forums/show...hlight=hacksaw

Jim243 · April 6, 2012, 10:29 PM

Quote:

Is this when slight pressure on plunger and bullet stops?

Yes, that is when I lock the LNL OAL gauge down. Should require only a slight push with a cleaning rod to have the bullet fall back out of the chamber.

Quote:

Also modified case headspace is 0.003" smaller than my fireformed brass so do I add that to my reading?

Yes. I like to use a 0.05 jump to lands on my loads, so I take the reading and subtract the 0.05 from that. That's just the way I do it and I get great results. Your rifles may be different and will have to try it a number of ways to see what works best for you.

Jim

PA-Joe · April 7, 2012, 06:45 AM

Jim243: using the Hornady Headspace bushing and I FL size to be a slightly less than slight crush fit in the chamber.

That slight crush could be not enough shoulder bump, too long a case (not trimmed) or your COL is too long and you are pushing the bullet in to the lands.

hooligan1 · April 7, 2012, 06:56 AM

I'm misunderstanding the question . Just push the bullet projector rod until the bullet stops moving forward, (I like to take a cleaning rod and insert it into muzzle and push the bullet back and forth until I'm certain it's touching rifling) then I lock the set screw down carefully, and withdraw the tool from the rifle,and measure OAL with your comparators.

F. Guffey · April 7, 2012, 07:20 AM

I move the altered/modified case straight to the seater die, adjust the seater die to the dimensions of the modified/altered case, I am the fan of transfers, standards and verifying, after adjusting the die to the transfer, I use a dial caliper to .000 (zero) the height of the seater plug stem above the die.

.000 as in zero off the lands, this is not something that must be discovered every day, my main interest when modifying a case to function as a transfer is to determine the length of the throat.

I have no interest in eliminating ‘the running start’, I am the fan of bullet jump.

F. Guffey

April 5, 2012, 12:15 AM	#1
browninghunter86 Senior Member Join Date: November 14, 2011 Posts: 524	Hrndy OAL Gauge Just got my OAL gauge and modified cases for it. Followed instructions and set up but *HOW DO YOU KNOW WHEN YOU OGIVE TOUCHES THE LANDS?** Is this when slight pressure on plunger and bullet stops? On my 308 with Hrndy 165 BTSP I am getting a reading of 2.249"(Ogive) 2.815". Also modified case headspace is 0.003" smaller than my fireformed brass so do I add that to my reading? Some people online are saying to add it to get most accurate reading I am getting that same reading everytime with every bullet I try so I am assuming this is correct. Any tips or tricks to this would be helpful

April 5, 2012, 01:51 AM	#4
Jim243 Senior Member Join Date: January 5, 2009 Location: Just off Route 66 Posts: 5,067	Browninghunter, when you said the headspace of the mod case was 0.003 shorter than your fired case, are you measuring from the shoulder or case mouth? Also do you use a collet die or full length die when you resize?? It never made, no ever mind for me since I want to know the Max OAL of the chamber with case and bullet and that is what the gauge is designed to do. The neck size on the mod case, plays no part in the measurement. Jim __________________ Si vis pacem, para bellum

April 7, 2012, 06:56 AM	#10
hooligan1 Senior Member Join Date: July 18, 2010 Location: Independence Missouri Posts: 4,587	I'm misunderstanding the question . Just push the bullet projector rod until the bullet stops moving forward, (I like to take a cleaning rod and insert it into muzzle and push the bullet back and forth until I'm certain it's touching rifling) then I lock the set screw down carefully, and withdraw the tool from the rifle,and measure OAL with your comparators. __________________ Keep your Axe sharp and your powder dry. Last edited by hooligan1; April 7, 2012 at 07:02 AM.

April 5, 2012, 12:41 AM	#2
deepcore Senior Member Join Date: July 24, 2010 Posts: 364	I adjust my readings to account for the difference in headspace between the Hornady modified case and my fired case. I myself use slight pressure. I previously pushed too hard and then having to push hard on the wooden towel to dislodge the bullet I could see the (rifling's) scratches down the side of the bullet.

April 5, 2012, 12:51 AM	#3
browninghunter86 Senior Member Join Date: November 14, 2011 Posts: 524	so if modified case is .003" less then add that to my final reading and should be gtg? When I used wooden dowel to get bullet out it barely is in there and comes out with hardly any resistance

April 5, 2012, 03:18 AM	#5
F. Guffey Senior Member Join Date: July 18, 2008 Posts: 7,249	The difference between the two measurements, the fired case is formed and should represent the distance from the bolt face to the shoulder of the chamber, the same information is available to a reloader that can measure the length of the chamber without firing a case (to fire form). When determining ‘maximum overall length’ with a transfer or Hornady gage the bolt is removed (on bolt guns), meaning the answer is yes, head space is added to the maximum overall length. Again, I am not the fan of seating the bullet to the lands, I am the fan of the running start, I want my bullets to hit the lands with a jump. The difference in price between a transfer and a Hornady gage is about $32.00 dollars plus $7.00 for the modified case, the transfer is free. For free, the reloader can use the transfer to adjust the seater die. http://www.dillonprecision.com/conte...ll_Length_Gage If the reloader uses a fire formed case when determining ‘maximum overall length’ the head space is included. That means the reloader will be required to neck size and drill and tap the primer pocket/flash hole to modify the case. And again, there is no guarantee the maximum overall length case will feed, some could require chambering one at a time. F. Guffey

April 5, 2012, 06:57 AM	#6
browninghunter86 Senior Member Join Date: November 14, 2011 Posts: 524	Jim243: using the Hornady Headspace bushing and I FL size to be a slightly less than slight crush fit in the chamber.

April 7, 2012, 06:45 AM	#9
PA-Joe Senior Member Join Date: June 9, 2010 Location: NEPA Posts: 909	Jim243: using the Hornady Headspace bushing and I FL size to be a slightly less than slight crush fit in the chamber. That slight crush could be not enough shoulder bump, too long a case (not trimmed) or your COL is too long and you are pushing the bullet in to the lands.

April 7, 2012, 07:20 AM	#11
F. Guffey Senior Member Join Date: July 18, 2008 Posts: 7,249	I move the altered/modified case straight to the seater die, adjust the seater die to the dimensions of the modified/altered case, I am the fan of transfers, standards and verifying, after adjusting the die to the transfer, I use a dial caliper to .000 (zero) the height of the seater plug stem above the die. .000 as in zero off the lands, this is not something that must be discovered every day, my main interest when modifying a case to function as a transfer is to determine the length of the throat. I have no interest in eliminating ‘the running start’, I am the fan of bullet jump. F. Guffey