Bullet Alignment Truing Fixture

[terry_g]

I made this over the past few days. It works quite well. I might add a spring loaded holder
for the primer end of the case later. I lined one end of the spindle that the bullet tip fits in with
1/4" OD plastic pilot line and the other end of the spindle with 3/8" OD plastic pilot line.
Out of 20 30-06 bullets I checked were mostly .002" to .003" run-out and easily straightened
to around .001".
I was surprised to find a few that were .004" and .005" run out.

Terry

 

[Alphawolf45]

I need more pictures of it actually in use to understand what it is.. Then too you could shoot some targets with the improved aligned cartridges and tell us if there was enough difference to justify the effort.

 

[terry_g]

Here is another picture with a bullet in the fixture. Holding the cartridge against the spindle and the V block and
rotating it you can see the run-out. By rotating the high spot against the screw that is adjacent to the dial indicator
and using the screw to push against the neck of the case the cartridge can be brought very close to true.

Terry

 

[Rbeckett]

Terry,
Does that improve the feeding between shots or does it improve the seal of the bullet in the mouth of the rifling? Just trying to get my head around why this would be important since it obviously is. The is a really neat straightening fixture to do it too.

Bob

 

[terry_g]

I am hoping for an improvement in accuracy. I have a 30-06 that is quite accurate but
I get a few fliers with it. It groups around 3/4" consistently at 100 yards but every 4 or 5 shots 1 will be
off by 2" or more.

Terry

 

[rdhem2]

Mr. terry_g can probably explain better than I can. But the use of his very sweet device is in the quest for the impossible. Or so it seems. To have a rifle, the ammunition, the weather, and yourself all cooperate at the same moment on a given day and at a given time to produce a five shot group only as large as one caliber. Yes, one hole. Just like shooting one bullet in a target and getting someone to believe four more followed the first one through.

Millions of dollars have been invested in gear and ammo by thousands of people and it has never happened yet.

 

[blacksmithden]

Very interesting. Not so much for myself since my built in shake from too many years of not enough sleep and too much coffee negates precision reloading at this level. It might however be something people would buy. Hmmmmm. It never ceases to amaze me the lengths people will go to in order to create ultra precision cartridges. Thanks for posting it.....and of course...Merry Christmas !

 

[MikeWi]

"It might however be something people would buy. Hmmmmm. "
There's a company (or was anyway) called Black Hills ammunition that sells custom loads that are supposed to be high accuracy.

I used to be very into the tuning aspect of handloads. I shoot a .308 Springfield Armory M1A1 National Match, and in spite of all the impressive sounding NM parts, it prints all over the place with any commercial load I've tried (even Black Hills), even at 100 yards. Handloads got that to 3/4" (3/4MOA) at 100 yards on the first try, and I've yet to see if I can take it further.

Among the mystic things you do to attain top accuracy (not necessarily in order, just as it comes to mind): uniform the primer pocket, deburr the flash hole, fire-form the brass (shooting new brass once thru the gun forms it to your chamber), Trim the case to the correct length, turn down the outside of the neck to obtain an even wall thickness in the neck, hand measure each powder charge, use bullets that have all been checked for uniformity of shape and weight, you can do the same to the cases to look for any that may have too thin or thick of a wall. Use a special gauge to measure the maximum length (bullet plus brass) that will fit into the chamber and then adjust your Over All Length to be just short of that so you can minimize the bullet jump ie. the distance traveled before the bullet hits the lands of the barrel. There's differing opinions as to the distance as I recall. The amount of crimp holding the bullet in the cartridge is also a factor. Oh and minimal resizing of the brass once it's formed of course.

It's been about 12 years since I've been doing that stuff, so I may have missed something.

So yeah, lots of ways to get there.:roflmao:

 

[Earl]

Ron Hoen, Lester Bruno and Fred Sinclair have sold these types of devices in the past. There are some other manufacturers as well. don't know if Sinclair still has them but I believe Lester does. I have one of Lester's that I keep in my Benchrest box. It has a .0005 indicator on it. We use them to verify the seating die and sizing die performance. In the Bench game, we do everything we can to make things consistent. With the bullets, powder, barrels, actions, stocks and triggers available today, 5 shot groups are regularly shot smaller than .2". Teen aggregates (5 targets, each with 5 shots that average .199 or less) happen at matches on a regular basis. I will not demean the 30-06 100 yard .750 groups. That is a fine group for a hunting rifle. I have an old Remington 700 in 30-06 that will allow me to get 3 (130 grain) bullets to sometimes touch at 200 yards. One of those little rounds went all the way thru a mule deer at 257 yards a couple years ago. That is fantastic for a hunting rifle. An inch or two makes very little difference to a deer. With load tuning, careful selection of bullets, powder and brass, we can easily make a gun go from 5 inch groups to 1 or two inch groups. If we are lucky to get a decent barrel from the manufacturer, those groups may shrink to the .75 or so as the original poster stated. In my experience that is about as good as it gets. The guns are built to SAMMI specs i.e., loose. To get the most out of a rifle, you need to have a close fit between the cartridge and the chamber. The bullet seating should allow the bullet to just touch the rifling or be just a few thousands off. Case necks are turned to the "tenth" to insure that each bullet is "gripped" with the same tension. etc, etc, etc. The list goes on. We go to great lengths to get that last quarter inch out of the group. Then we go to greater lengths to get the last hundred thou out of the group. Then we spend even more on things like bullet straighteners that at least make us think that they help reduce our group size. Do they? Don't know but I do know that they won't help much if at all on a hunting rifle. But if they make you more confident that you have the best ammo available, then they indeed have some value. Just my view of things.
Earl

 

[Earl]

Here is another picture with a bullet in the fixture. Holding the cartridge against the spindle and the V block and
rotating it you can see the run-out. By rotating the high spot against the screw that is adjacent to the dial indicator
and using the screw to push against the neck of the case the cartridge can be brought very close to true.

Terry

The fixture that I use has the indicator riding on the bullet, not the case.