Active TopicsActive Topics  Display List of Forum MembersMemberlist  Search The ForumSearch  HelpHelp
  RegisterRegister  LoginLogin  

Home | Load data | Articles | Ballistic Calc | Energy Calc
Long Guns
 Handloads.Com Forum : Long Guns
Subject Topic: set back off lands? Post ReplyPost New Topic
Author
Message << Prev Topic | Next Topic >>
roysclockgun
Newcomer




Joined: March 27 2018
Location: DeLand, FL
Posts: 2
Online Status: Offline
Posted: March 27 2018 at 8:24am | IP Logged Quote roysclockgun

When I began hand loading for rifles in the 1960s, the general belief was to load the bullet very close to the lands. Later that belief was replaced by, "give the bullet some jump to the lands to decrease pressures and raise MV." So, what is a good starting point for me when loading 280Rem, using 120gr. Nosler Ballistic Tip bullets?
I have been able to ascertain the OAL of the bullet in the case to where the bullet does touch the lands. How far off the lands should I begin in order to get best accuracy and highest MV?
Thank you!

__________________
StevenA
Back to Top View roysclockgun's Profile Search for other posts by roysclockgun
 
Rex
Senior Member




Joined: June 01 2004
Location: ;Paxton, Ne.
Posts: 3547
Online Status: Offline
Posted: March 27 2018 at 9:49am | IP Logged Quote Rex

Roy, Welcome to the forum.
I just use the loading manual recommendation for over all length.
I have a Swedish Mauser that has enough throat that I can drop in a bullet, set an unloaded case on top of it and close the bolt and hear the bullet rattle around.
It still shoots nice groups. This little Mauser has taught me to not pay so much attention to the speed, just find the best grouping staying within book loads.
Rex
Back to Top View Rex's Profile Search for other posts by Rex
 
Ham Gunner
Senior Member


Avatar

Joined: August 12 2007
Location: Ozark, Missouri
Posts: 5435
Online Status: Offline
Posted: March 27 2018 at 12:28pm | IP Logged Quote Ham Gunner

I have always checked the bullet seating and found where the bullet just touches the lands and then back off a few thousandths to start my load work up.

With cast bullets, I have always read that one needs to have the bullet seated out far enough that the cast lead bullet slightly engraves the lands for best accuracy and to prevent bullet damage caused by skidding of the soft alloy bullet prior to it engaging in the rifling enough to start it's normal spin with the rifling twist.

From ACCURACY BY THE THOUSANDTHS:by Troy Lawton
United States Army Marksmanship Unit

"When loading for maximum accuracy, it’s best to start by seating bullets shorter than the maximum COAL at which the bullet engages the rifling. Loading so that bullets touch the rifling increases chamber pressure, while allowing some “jump” to the rifling eliminates this issue. One good COAL to begin accuracy testing is by seating the bullet 0.020” off the rifling. As accurate loads are developed, this COAL may be fine-tuned by decreasing bullet jump to 0.010” or increasing to 0.030”, etc.. Loading with bullets “just touching” the lands can sometimes reduce accuracy, as individual bullet variations may cause some to jump to the rifling, and others to engage it, reducing consistency.

Once you find a given bullet with a given powder (and even batch of powder) at a given powder measurement that works in a rifle well, that is the place you want to be to begin testing the rifle with COAL. Bringing the bullet forward and moving it backward even a few thousands can have measurable outcomes."

By the Thousandths

Edited by Ham Gunner on March 27 2018 at 12:31pm


__________________
73 de n0ubx Rick - NRA BENEFACTOR LIFE MEMBER/VFW LIFE MEMBER - A government big enough to GIVE you
everything you want, is strong enough to TAKE everything you have. - Thomas Jefferson

Back to Top View Ham Gunner's Profile Search for other posts by Ham Gunner
 
RECURVE
Senior Member


Avatar

Joined: December 23 2003
Location: United States
Posts: 517
Online Status: Offline
Posted: March 27 2018 at 3:34pm | IP Logged Quote RECURVE

What Ham said
Back to Top View RECURVE's Profile Search for other posts by RECURVE
 
hoghunter
Senior Member




Joined: March 01 2010
Posts: 464
Online Status: Offline
Posted: March 28 2018 at 5:45pm | IP Logged Quote hoghunter

First you need a reliable method to measure the distance from the lands for the specific type of bullet you are going to use. The simplest, cheapest and easiest tool I ever used in the Frankfort Arsenal tool available at Midway.

Second, keep in mind that measurement is not absolute. Because of variations in bullet ogive that measurement will vary slightly from bullet to bullet even with high quality bullets.

Third, the seating depth must be sufficient to allow the cartridge to fit the magazine and provide adequate bullet tension. A good rule of thumb is seating the bullet at least one bullet diameter into the case.

I start a .020" off the lands but never go closer than .010" as a safety precaution. Jamming the bullet into the lands can create high pressure,can be dangerous and is a terrible idea for a hunter.

Each rifle can be different so some testing may be needed for optimum seating depth. While most rifles prefer a short jump some do better with a longer jump depending on bullet design. Sierra wrote an article several years ago about this and I found it to be true.

First priority should be safety followed by functionality followed by accuracy. Since you're shooting a 280 Rem I assume this is for hunting purposes. You don't need a tack driver for a big game rifle. 1 moa is great, 1 1/2 moa is good, 2 moa will work for most big game hunting situations.
Back to Top View hoghunter's Profile Search for other posts by hoghunter
 
roysclockgun
Newcomer




Joined: March 27 2018
Location: DeLand, FL
Posts: 2
Online Status: Offline
Posted: March 28 2018 at 6:19pm | IP Logged Quote roysclockgun

Thanks All for the well thought out responses. I do shoot 280Rem and 7mm-08, because I believe that 7mm bullets do fly well and hit hard.
I realize that many "hunters" that I see at my local range, two days before opening day, are very satisfied to put three bullets into a dinner plate at 100 yards, but that is not me.
I still work for getting five rounds fired from a cool barrel, to all touch at 100 yards. Granted, not world class, but will guarantee me that if I do my part, the rifle is ready to work for me on quick, humane kills on anything that I bring under fire.
I do not stretch my range beyond what I know that I can do. My longest ever shot was just over 400 yards on a mule deer buck that I had stalked all morning and finally had him looking back at me, from across a canyon.
I've killed bull elk with the same rifle, when younger men had told me that I was "under gunned" using 280Rem on bull elk. Wrong!!
The same rifle has cleanly bagged white tail, wild hogs, pronghorn and prairie dogs.
After decades of jumping from one caliber to another, I am listening to what Jack O'Connor said; "Beware the man who only owns one rifle. He can probably shoot it!" I own lots of rifles, but for years now, the Browning Stalker in 280Rem is the go to rifle when I want to kill.
Best,
Steven


__________________
StevenA
Back to Top View roysclockgun's Profile Search for other posts by roysclockgun
 
M700
Senior Member


Avatar

Joined: June 12 2004
Location: Washington
Posts: 6350
Online Status: Offline
Posted: March 28 2018 at 6:24pm | IP Logged Quote M700

Howdy Steven! Nice to see you here.

Steven is a friend, who invited me to join him on a mule deer hunt some years ago. He's quite the marksman & hunter. We both tagged good mule deer & pronghorn antelope on that trip.

And yes, he was using that .280 with the 120 Nosler then too! It's a great hunting bullet.

Regards, Guy
Back to Top View M700's Profile Search for other posts by M700
 
hoghunter
Senior Member




Joined: March 01 2010
Posts: 464
Online Status: Offline
Posted: March 29 2018 at 3:18pm | IP Logged Quote hoghunter

Jack O'Connor was a hunter supreme. He is largely responsible for the popularity of the 270. He was a man who possessed incredible common sense.

In my humble opinion there is too much emphasis today on selection of calibers when there should be more on field marksmanship. I don't mean shooting off the bench. I mean shooting if a field position and knowing your capability.

Just about any center fire big game cartridge will work just fine in the hands of a skill rifleman. However to become really skilled you need to shoot year around and practice under field conditions.

Sounds like you're headed in the right direction. I don't think you're under gunned with a 280 Remington.My ex-boss who was born and raised in Wyoming has taken a number of Elk over the years with a 270 using factory ammo. He's an exceptional hunter and field shot.

Back to Top View hoghunter's Profile Search for other posts by hoghunter
 

Home | Load data | Articles | Ballistic Calc | Energy Calc

If you wish to post a reply to this topic you must first login
If you are not already registered you must first register

  Post ReplyPost New Topic
Printable version Printable version

Forum Jump
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot delete your posts in this forum
You cannot edit your posts in this forum
You cannot create polls in this forum
You can vote in polls in this forum

Powered by Web Wiz Forums version
Copyright ©2001-2008 Web Wiz Guide

This page was generated in 0.1406 seconds.