Is there any consensus among the forum members here that the less distance your boolet has to jump into the lands the better?

Hello,
When actively shooting long range matches,cal.308, it was common practice to seat the bullet anywhere from 2-.005 off the lands and grooves. It seemed to work well for me, but there were some competitors,even well known match winners that reportedly did not seat their bullets that close to the lands and grooves, but some 15-.020 off. I still load rounds for sporting/hunting rifles approx. .005 back and just a habit I guess. Have seen some factory sporting rifles that in order to seat the bullet that close, the throat is so long that you have no case neck left or very little, so you would have to judge your particualr rifles chamber throat and go accordingly. Kind of a rule of thumb is to have one caliber of the bullet seated in the neck if you can do so. Good luck

martin

Shooting Centerfire Benchrest Competitively, I seated bullets .010 for best accuracy in my rifles "back then". That was circa 1970.
I just carried that over to my sporters today, and I get good accuracy.
Is .010 best for every rifle? Probably not. But, I'm just too old to change, or to experiment as I get some awesome accuracy with that bullet seating.
Of course, if the magazine lenght dictates other wise, I go with the magazine length as I want to feed hunting rifles ammo from the magazine.
You young guys can experiment..LMAO
I'm open to changing to other lengths too.

Don

quote:

How far do your bullets "jump"?

just as far as they have to.

In hunting rifles this is a much overworked issue.

Every rifle is diff. & diff. bullets like diff. "jumps". Barnes are a good example. They prefer much more distance to lands for best accuracy, at least in my rifles. Start @ 0.01" off the lands & work it down & see how she shoots. Obviuosly w/ some rifles, mag length dictates OAL.

quote:

Originally posted by fredj338:
Every rifle is diff. & diff. bullets like diff. "jumps"..

Many of my deep throated rifles have quite large bullet jumps and yield great field accuracy. The most accurate of these is the 12BVSS .223.The 33 and 34 grain bullets probably don't come within .050" of an inch of touching and still produce MOA.
The 7 X 41 using the 140 grain bullets fits in the same catagory.
I may be out of the norm but when dealing with good repeatability , bullet jump is like frosting on the cake. The ingrediants IN the cake play a far more important role. The frosting just makes a good cake taste better. roger

quote:

Originally posted by Jimmy P Coaltrain:
Is there any consensus among the forum members here that the less distance your boolet has to jump into the lands the better?

no

I'm under the same belief as many here. The recipe has far more meaning than the jumping distance .

I generally on target rifles set .010 -.005 depending on caliber load pressures .

Big magnums .015 or more I dislike sudden pressure spikes . IMO case and load preparation along with

bullet selection is by far more important than jump . BR shooters have made a believer out of me on that !.



Then again if your simply asking about the boolet jumping , then only as far as I'm able

to make the surface of which their setting on move .

No concencus Given we often have to live with magazine constraints, we don't always get to play right at the lands.

I've worked up loads with the bullets .025" off the lands that print 1/2", and I've been right on the lands and been unable to group under 1 1/2".

If my mag allows it, I'll start my load work with bullets kissing the lands, and if I'm not getting the groups I want with a max charge, I'll try seating 10, 25 and 50 thou off.

If I have to start 25 to 50 off due to mag constraints, then thats where I seat and I tune with powder charge weight.

This whole crap about bullets seated at a magic distance from the lands is a hoax thought up to sell you all kinds of gimicks etc... Just seat them so that they will fit in the rifles magazine and feed properly-the shorter the better(shot world record breaking groups this way)!

I don't really know how far I set my bullets off the lands, but I can tell you it's such that 1/4-turn of the seating screw allows the round to spin easily in this dummy chamber my gunsmith made for me. He used the same reamer used to cut the chamber in the barrel. This dummy was either the first or second use of the reamer, so it's as close to the real thing as possible. The bore is .300; the second diameter is SAAMI for the 300WSM neck and the shoulder is cut exactly at the datum diameter for that cartridge at that point. I think everyone who reloads should have one of these. Makes setting bullets and sizing the cases very easy...

Shootaway....please tell us about your success as a world record breaker. Your system sounds wonderful.

I will give you one thing...you are a world record breaking entertainer here on the chatrooms!!

looks like no consensus other than the jump does make a difference. Paul the into the lands if you can works for me!

quote:

Originally posted by kraky:
Shootaway....please tell us about your success as a world record breaker. Your system sounds wonderful.

I will give you one thing...you are a world record breaking entertainer here on the chatrooms!!

you got that right!

Hey Rolltop, You heard from Vapo?

Hey Jimmy, Some of my "Who buys the BBQ?" Loads are Seated 0.005"<->0.010" Into-the-Lands and were Developed that way intentionally.

All of my Hunting Loads set back from the Lands a bit. Some are controlled by the Magazine length, due to the Sleekness of the Bullet allowing them to Seated so far forward. A Bullet with a Lower B.C. is often enough to offset the situation and I can go close to the Lands again.

Most of the Hunting Loads are Developed just off the Lands(again depending on the Magazine and Bullet being used). Once the best Harmonic Node is located, then I adjust the Seating Depth to Fine Tune the Final Load.
-----

But there are always exceptions which create the confusion. I have one 35cal rifle that using a specific "Light for Caliber" Bullet, just won't reach the Lands and remain inside the Case Neck. The Bullet has a Cannelure, so I just Seated them to the Cannelure and as an after thought applied a slight Roll Crimp.

Decided to Measure and see just how far Off-the-Lands they were and it is something like 0.264"<->0.268"(more than 1/4"), without me going to check the actual distance. Had no idea how they would shoot, so I shot 9 shots at one Target over the course of about 12hrs. All the Holes were inside a 1" square with room to spare.

I'd have lost money on that bet.
-----

I'll agree with those that believe there is no specific Rull-of-Thumb for Hunting Load Seating Depths.
-----

One thing you can count on for absolutely, positively, sure, without a doubt - nothing draws Flies like a fresh pile of obummer. - Hot Core

quote:

Originally posted by Hot Core:
Hey Rolltop, You heard from Vapo?

Here's his last post.

Hey Rolltop, Thank you.

quote:

Originally posted by Hot Core:
You heard from Vapo?

He's been busy helping me. roger

quote:

Originally posted by bartsche: I may be out of the norm but when dealing with good repeatability , bullet jump is like frosting on the cake. The ingrediants IN the cake play a far more important role. The frosting just makes a good cake taste better. roger

U nailed that shot for a 10X!!!

Don

quote:

Originally posted by bartsche:

quote:

Originally posted by Hot Core:
You heard from Vapo?

He's been busy helping me. roger

Hey Bartsche, Just didn't want to loose track of him like we did Alberta Canuck.

Speaking of lost, did "Bill Mc" fall into his still?

Mine don't jump any. They enter the rifling before the rear end has left the cartridge mouth.

I am no old hat at the reloading and am only a game shot, i have a .308, the bullets that i use are Horn SP and they have a crimp, seating the bullet just off the rifling, however this leaves the crimp of the bullet well clear of the brass! any advice? I have shot some and they shoot well, just dont know if i can crimp to finnished bullet surface as i can pull the bullets out by hand with some effort i might add.

I have found adjusting bullet jump very useful for final tuning of a load receipe which is already working pretty well in any particular rifle of mine. It doesn't seem to help a lousy load, and is the last variable I usually adjust in the good loads.

When adjusting it, I usually start about .002" off the lands and work away from the lands in about .003" increments for "hunting-size" rounds and rifles.

For BR ammo I work in considerably smaller increments than that, and start with the bullet touching the lands. I have had no marked success with BR loads which are set INTO the lands, though some folks do very well that way.

Why do I spend that time on hunting ammo? Because I can, and I enjoy seeing how well my rifles can do, regardless their purposes.

Does it make the animals any deader? No, but it makes me feel more alive. That's a deal I'll take any day.

quote:

Originally posted by Jimmy P Coaltrain:
Is there any consensus among the forum members here that the less distance your boolet has to jump into the lands the better?

The thing that counts is group size. Bullet jump is just one of many parameters that may be varied in the effort to establish a reliable, repeatable, load that shoots into groups of equal to or less than the desired maximum size group.

In other words, what ever works is what you use, within reason. The realities of living with real world situations dictate the "reason". For example:

Jamming bullets into the lands in a hunting rifle makes no sense because it makes unloading the rifle problamatic - the bullet may pull out of the case and dump the action full of powder. Not cool! I don't like it in a match rifle either but some bullets just demand to be jammed or they don't shoot worth pooh.

Setting bullets out to the point the ammo won't fit or feed from the rifles magazine doesn't work for hunting rifles or repeater match rifles. It may be used in match single shot bolt rifles with a single shot follower installed.

Fitch

whatr shoot-for-brains ACTUALY said

quote:

Originally posted by shootaway:
...crap ... magic ... hoax ..gimicks ....the shorter the better

quote:

Originally posted by shootaway:
shot world record breaking groups this way

you did? you have bonafied 0.0XX groups, shot with a certified judge? of, you were just LYING again?

quote:

Originally posted by foxshot:
...seating the bullet just off the rifling, however this leaves the crimp of the bullet well clear of the brass! any advice? I have shot some and they shoot well, ...

Hey FoxShot, As long as "they shoot well", meaning they are accurate enough to meet your needs, then there is no real reason to mess with them.

There are some Cartridges, firearm styles, and specific usages where having the Bullet Crimped is essential to make sure the Bullet does not move due to the recoil of other Cartridges being fired. If you are using a Bolt Action and Hunting Non-Dangerous Game, then it probably doesn't matter if you Crimp or not. There have been lengthy discussions on Crimping in the past and will be again.

On the other hand, a lot of us enjoy the challenge of getting the Groups as small as "reasonably" possible for a regular old Hunting Grade rifle. To this end we expend all kinds of time, energy and components. Sometimes the groups do get considerably smaller and occasionally they don't.

The nice thing about it is "you" get to decide when the Load meets your requirements. Then you can relax a bit and simply enjoy the shooting.

Good Hunting and clean 1-shot Kills.