Calguns.net  

Home My iTrader Join the NRA Donate to CGSSA Sponsors CGN Google Search
CA Semiauto Ban(AW)ID Flowchart CA Handgun Ban ID Flowchart CA Shotgun Ban ID Flowchart
Go Back   Calguns.net > FIREARMS DISCUSSIONS > Centerfire Rifles - Manually Operated
Register FAQ Members List Calendar Mark Forums Read

Centerfire Rifles - Manually Operated Lever action, bolt action or other non gas operated centerfire rifles.

Reply
 
Thread Tools Display Modes
  #41  
Old 11-02-2019, 2:33 PM
Preston-CLB's Avatar
Preston-CLB Preston-CLB is online now
Senior Member
 
Join Date: Apr 2018
Location: Sierra Foothills N of Yosemite
Posts: 507
iTrader: 0 / 0%
Default

This has been an intreesting discussion. Thanks for all the great info!

I closely inspected the bolt head on my Savage .223 yesterday. It is nice and smooth, and flat.
-p
__________________
“If you want nice fresh oats, you have to pay a fair price. If you can be satisfied with oats that have already been through the horse, well, that comes a little cheaper"
Reply With Quote
  #42  
Old 11-07-2019, 6:25 AM
LynnJr LynnJr is offline
Calguns Addict
 
Join Date: Jan 2013
Posts: 6,643
iTrader: 7 / 100%
Default

Tightening the bolt body accomplishes even less than it does on the R700 because the cocking piece is at 3:00 instead of 6:00 on the Remington. It's pushing the bolt into the opposite lug raceway, not on to the upper bearing surface. On top of that, the bolt head floats. Spoiler alert, when the gun is fired, the pressure holding the bolt body up or over is released and the bolt body is floating when the primer goes off. Yes, tight bolts feel nice to operate.

I missed this earlier.
In the old days it was common to see a Savage type floating bolthead on a 700 Remington. It was cheaper/easier to sleeve or double sleeve the bolt body so it was short lived.
And not really a spoiler alert the sleeved double sleeved guns outshoot the unsleeved guns even though the bullet is out of the barrel before the gun moves 0.050 of an inch.
The Borden "Bumps" found that you can combine a loose fitting bolt with a tight lockup and get the best of both worlds.
__________________
Lynn Dragoman, Jr.
Southwest Regional Director
Unlimited Range Shooters Association (URSA)
www.unlimitedrange.org
Not a commercial business.
URSA - Competition starts at 2000 yards!
Reply With Quote
  #43  
Old 11-08-2019, 8:42 AM
ShaunBrady ShaunBrady is offline
Member
 
Join Date: Oct 2011
Posts: 186
iTrader: 0 / 0%
Default

Quote:
Originally Posted by LynnJr View Post
And not really a spoiler alert the sleeved double sleeved guns outshoot the unsleeved guns even though the bullet is out of the barrel before the gun moves 0.050 of an inch.
Do you have a test that demonstrates this?

Vaughn was pretty dismissive of the practice of tightening bolt bodies in his book "Rifle Accuracy Facts". He used a Remington 721 for his testing, which has a fixed bolt head like the 700.

In the same chapter that he disses bolt tightening, he demonstrates that the underhung recoil lug and asymmetry in the receiver holes ahead of the bolt lugs are the larger issues.

On a Savage, it has absolutely no potential value because of the floating bolt head and the firing pin loads the bolt body into the opposite bolt raceway.

The 700 is actually closer to the Savage than the tight bolt crowd thinks. The simple demonstration is to cock an empty R700 and try to move the bolt up and down. It's pretty tight. Fire the empty gun and try to move the bolt again. Now it rattles like a Savage. That's the condition it goes off in. When the firing pin hits the primer, the whole R700 bolt is floating just like the Savage bolt head, not preloaded by the trigger and firing pin. As the bullet starts moving, the bolt thrust from the cartridge loads the bolt into the lugs, not the trigger and firing pin.

When you lap the lugs on a R700, you pull the firing pin, right?
Reply With Quote
  #44  
Old 11-08-2019, 10:23 AM
ar15barrels's Avatar
ar15barrels ar15barrels is offline
I need a LIFE!!
 
Join Date: Jan 2006
Location: Van Nuys
Posts: 46,772
iTrader: 101 / 100%
Default

Quote:
Originally Posted by ShaunBrady View Post
Do you have a test that demonstrates this?

Vaughn was pretty dismissive of the practice of tightening bolt bodies in his book "Rifle Accuracy Facts". He used a Remington 721 for his testing, which has a fixed bolt head like the 700.

In the same chapter that he disses bolt tightening, he demonstrates that the underhung recoil lug and asymmetry in the receiver holes ahead of the bolt lugs are the larger issues.

On a Savage, it has absolutely no potential value because of the floating bolt head and the firing pin loads the bolt body into the opposite bolt raceway.

The 700 is actually closer to the Savage than the tight bolt crowd thinks. The simple demonstration is to cock an empty R700 and try to move the bolt up and down. It's pretty tight. Fire the empty gun and try to move the bolt again. Now it rattles like a Savage. That's the condition it goes off in. When the firing pin hits the primer, the whole R700 bolt is floating just like the Savage bolt head, not preloaded by the trigger and firing pin. As the bullet starts moving, the bolt thrust from the cartridge loads the bolt into the lugs, not the trigger and firing pin.

When you lap the lugs on a R700, you pull the firing pin, right?
I have Vaughn's book.
Have you read Greg Tannel's take on bolt tilt?

Here is my take on 700 bolt clearance:
Even though the bolt is LOADED by the cocking piece, the fixed bolt head causes the lugs to lift off the lug abutments due to the bolt sitting at an angle in the receiver bore.
When you release the striker, that loading goes away as you note.
When you release the striker, a great amount of force gets applied to the bolt lugs and reciever abutments by the consumption of powder and pushing a bullet down the bore.
That force causes the lugs to want to be flat to each other.
Gravity makes the bolt body want to FALL when the loading goes away that WAS holding the bolt body against the top of the reciever.
So when the loading goes away, you have gravity AND firing forces acting on the bolt.
Since there is room to move in the reciever, you have turned the bolt body into a tuning fork.
The bolt body bounces up and down in the reciever and that sets off an additional vibration harmonic through the barrel.

Reducing the clearance between bolt body and fixed bolt reduces the amplitude of that harmonic.

Even the firing pin smacking into the bolt creates a dramatic vibration.
The sloppiness of a fixed bolt within the reciever determines if that vibration will throw the gun off target or not.
Customers always want to know HOW MUCH accuracy truing a 700 is going to give.
There is no absolute answer because every gun is different.

One thing I tell them to do is to dry fire their gun and watch the crosshairs while firing.
Some guns will sit perfectly on target while others will jump 1/4moa or more.
The guns that jump the most will benefit the most as tightening up the bolt clearance reduces the jump.
__________________
Randall Rausch

AR work: www.ar15barrels.com
Bolt actions: www.700barrels.com
Foreign Semi Autos: www.akbarrels.com
Barrel, sight and trigger work on most pistols and shotguns.
Most work performed while-you-wait, evening and saturday appointments available.
Reply With Quote
  #45  
Old 11-08-2019, 4:02 PM
LynnJr LynnJr is offline
Calguns Addict
 
Join Date: Jan 2013
Posts: 6,643
iTrader: 7 / 100%
Default

The test is your target. Shoot one group with a tight bolt and a second group with a factory bolt.
We need to get you to our local range and behind a couple of my guns.
As Randall posted it's about things slapping around while the bullet is in the bore. You can put a live round in your gun and measure the difference from the top of the bolt shroud in a loaded condition and a fired condition.
For those looking for the thrill of there life grab hold of the middle of your barrel while someone fires the gun.
It's something you usually do once. Try it with a factory bolt and a tight bolt.
I think Al Harrell did some modeling of a loose fitting bolt on his website but it might have been on one of the more accuracy oriented websites after he posted some of his results.
The pictures show a couple of my BAT actions and recoil lugs are not used. The one in the picture is just there so I don't lose it. The more accuracy oriented the gun becomes the less the chance it will use a sandwiched recoil lug.

https://youtu.be/EiVv_vO9MI8

Here is a crummy video showing the bolt fit we are talking about. On a sloppy fitting bolt the firing pin spring will try and lift the bolt body up on a 700 action because both the cocking piece and the trigger use slanted engagement points. Some actions use 90 degree contact and this isn't an issue.
When the gun goes bang and that 50,000 psi hits the boltface it violently rattles the gun.
Attached Images
File Type: jpg IMG_20191108_162003769.jpg (93.1 KB, 13 views)
File Type: jpg IMG_20191108_162023692.jpg (91.5 KB, 10 views)
__________________
Lynn Dragoman, Jr.
Southwest Regional Director
Unlimited Range Shooters Association (URSA)
www.unlimitedrange.org
Not a commercial business.
URSA - Competition starts at 2000 yards!

Last edited by LynnJr; 11-08-2019 at 4:35 PM..
Reply With Quote
  #46  
Old 11-15-2019, 10:41 AM
kevins750's Avatar
kevins750 kevins750 is offline
Senior Member
 
Join Date: Feb 2013
Location: Deep behind liberal lines
Posts: 1,183
iTrader: 36 / 100%
Default

------------------------------------UPDATE----------------------------


heard back from savage...…..

they reamed the chamber
polished the chamber
replaced ALL extraction components

are awaiting a firing test..
__________________
"To compel a man to furnish funds for the propagation of ideas he disbelieves and abhors is sinful and tyrannical." Thomas Jefferson
NRA+CRPA member

"Get yourself a Glock and lose that nickel plated sissy pistol" -------Deputy Samuel Gerard
Reply With Quote
  #47  
Old 11-15-2019, 12:25 PM
ShaunBrady ShaunBrady is offline
Member
 
Join Date: Oct 2011
Posts: 186
iTrader: 0 / 0%
Default

Quote:
Originally Posted by kevins750 View Post
------------------------------------UPDATE----------------------------


heard back from savage...…..

they reamed the chamber
polished the chamber
replaced ALL extraction components

are awaiting a firing test..
Sounds like the belt and suspenders approach, it'll probably be fixed when you get it back.
Reply With Quote
  #48  
Old 11-15-2019, 12:29 PM
ShaunBrady ShaunBrady is offline
Member
 
Join Date: Oct 2011
Posts: 186
iTrader: 0 / 0%
Default

Lynn & Randall,

I'll add trying Bordon Bumping to my list of tests to do someday. I'm still skeptical, Vaughn was the guy with the test instrumented receiver.
Reply With Quote
  #49  
Old 11-15-2019, 7:20 PM
ar15barrels's Avatar
ar15barrels ar15barrels is offline
I need a LIFE!!
 
Join Date: Jan 2006
Location: Van Nuys
Posts: 46,772
iTrader: 101 / 100%
Default

Quote:
Originally Posted by ShaunBrady View Post
Lynn & Randall,

I'll add trying Bordon Bumping to my list of tests to do someday. I'm still skeptical, Vaughn was the guy with the test instrumented receiver.
I did them by tig welding bumps and then OD grinding them back to the diameter I wanted.
Works really slick.
__________________
Randall Rausch

AR work: www.ar15barrels.com
Bolt actions: www.700barrels.com
Foreign Semi Autos: www.akbarrels.com
Barrel, sight and trigger work on most pistols and shotguns.
Most work performed while-you-wait, evening and saturday appointments available.
Reply With Quote
  #50  
Old 11-16-2019, 8:57 AM
Preston-CLB's Avatar
Preston-CLB Preston-CLB is online now
Senior Member
 
Join Date: Apr 2018
Location: Sierra Foothills N of Yosemite
Posts: 507
iTrader: 0 / 0%
Default

Target-223-1.jpg

Here's some cherry picked groups from a couple of range days in October/early November.

Savage Model 10 Trophy Hunter XP
Wood stock
.223 Remington
22" Barrel
Leupold 4.5x14 VX3
Factory Federal Fusion MSR, 62 gr.

Distance: 100 meters
Weather: Clear, cool, calm wind.

(The center bullseye is 1" dia.)

This is a bone stock rifle. I was using Caldwell bag rests. I am quite happy with this rifle.
--P
__________________
“If you want nice fresh oats, you have to pay a fair price. If you can be satisfied with oats that have already been through the horse, well, that comes a little cheaper"
Reply With Quote
  #51  
Old 11-19-2019, 9:37 AM
ShaunBrady ShaunBrady is offline
Member
 
Join Date: Oct 2011
Posts: 186
iTrader: 0 / 0%
Default

Quote:
Originally Posted by LynnJr View Post
The test is your target. Shoot one group with a tight bolt and a second group with a factory bolt.
I gave that a try yesterday.



Didn't see a change.

The gun is a 300wm Remington 5R that had the same problem the OP did with his Savage, no primary extraction. The bolt was also the roughest I've ever felt. I smoothed it out some, but it's never going to be right.

I pulled the barrel and opened the counterbore to clear a PTG bolt with a M16 extractor. That bolt is from my first URSA gun. I have another factory 300wm bolt that has plenty of primary extraction. The bolt raceway on this gun measures 0.7035" with a snap gauge. The PTG bolt is 0.6995", and the Remington bolt is 0.692". Those 2 bolts headspace to within .002", but they're about .004" shorter than the bolt that came with the gun.

I took 0.006" off the shoulder of the barrel to bring the headspace down to the minimum with the replacement bolts. The go gauge is a little tight on the longer bolt, but it closes without much effort. I lapped the barrel/receiver threads and the receiver/recoil lug/barrel shoulder, then torqued it back together at 75 ft-lbs.

The best group was about 3/4 moa after reassembly, just over 1 moa had been it's previous best with the same box of ammo. The barrel had 36 rounds through it before I started fireforming a box of 100. The barrel sped up 34 fps as the 100 were fired.



That was shot with the Remington bolt.

The load was for fireforming and pretty mild. Weight sorted Winchester brass, H4831, 210, and 208 Amax 5 thou into the lands.



It's better ammo than you can buy, but not tuned to the gun in any way. I have no idea why the velocity spread is so low. It was that way all the way through the box of 100.

I'll repeat the test as I develop a load, but so far there is no discernible difference with the tighter bolt.
Attached Images
File Type: jpg IMG_2783.jpg (99.3 KB, 38 views)
File Type: jpg IMG_2785.jpg (93.9 KB, 35 views)
File Type: jpg IMG_2790.jpg (9.4 KB, 34 views)
Reply With Quote
  #52  
Old 11-19-2019, 10:06 AM
ShaunBrady ShaunBrady is offline
Member
 
Join Date: Oct 2011
Posts: 186
iTrader: 0 / 0%
Default

Quote:
Originally Posted by ar15barrels View Post

Customers always want to know HOW MUCH accuracy truing a 700 is going to give.
There is no absolute answer because every gun is different.
When I started building precision rifles as a hobby, I had a plan. I thought it was a good plan. I was going to change 1 thing at a time and test the accuracy at each step.

I started with a short action Stevens 200. I rebarreled it in 6xc with a budget unlapped Shilen blank that was $160 at the time. The idea was to try a better barrel next, and start in on receiver work after that.

This is what happened:



No truing or tight bolts, an engineer running the lathe, and a 2# trigger.

A few chambering projects later, I accepted that my old 300wm Sendero was never going to shoot and was just another donor gun. It would shoot 3 into a moa and then start drifting towards 5:00 at about a 1/4" a shot. I thought it was the barrel. I set the receiver up for a short true with a mandrel in the bolt bore, then checked the face and periphery. The face was out .003", and it was a low spot without a corresponding high spot 180 degrees away. I'm not sure how that happened, it didn't look like it was dropped, but Remington probably made a bunch of them that way that day. I'm pretty sure if I had not trued it, the new barrel would have had problems similar to the old.

Vaughn had a fixation on the tenon threads, and the Sendero experience reinforced that for me.

I think the answer to how much accuracy truing gives is it gives nothing, unless it does, and we're not going to have much of an idea until we're ready to remove metal.
Attached Images
File Type: jpg IMG_0592.jpg (88.1 KB, 35 views)
Reply With Quote
  #53  
Old 11-19-2019, 6:31 PM
LynnJr LynnJr is offline
Calguns Addict
 
Join Date: Jan 2013
Posts: 6,643
iTrader: 7 / 100%
Default

Shaun neither of your bolts is what is called a tight fit and your model 200 wouldn't show any improvement due to the floating bolthead..
If sloppy fitting bolts won matches shooters would be using them.
We need to get you to the range and shooting from a mechanical rest off of a concrete bench.
Did you try holding the barrel?
https://youtu.be/EiVv_vO9MI8
__________________
Lynn Dragoman, Jr.
Southwest Regional Director
Unlimited Range Shooters Association (URSA)
www.unlimitedrange.org
Not a commercial business.
URSA - Competition starts at 2000 yards!

Last edited by LynnJr; 11-21-2019 at 6:20 AM..
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump



All times are GMT -8. The time now is 1:07 PM.




Powered by vBulletin® Version 3.8.9
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
Proudly hosted by GeoVario the Premier 2A host.
Calguns.net, the 'Calguns' name and all associated variants and logos are ® Trademark and © Copyright 2002-2018, Calguns.net an Incorporated Company All Rights Reserved.
Calguns.net and The Calguns Foundation have no affiliation and are in no way related to each other.
All opinions, statements and remarks made by Calguns.net on this web site and elsewhere are solely attributable to Calguns.net.