So I built this simple tool...

[RotARy15]

Now what do I do with this info?

I was curious as to the length of my .308 Savage's chamber. And rather than buy a tool, I made one.

I took a piece of fire formed brass and neck sized it just enough to hold a bullet. Kinda the same way that you would in order to find the lands. I then cut the neck in half and chamfered/cleaned up the pieces. Finally, I seated a bullet (168gr Hornady) and just rested the piece of neck brass around the bullet as pictured below.

Shoved it in the chamber and got this.

I measured the brass length and it came to 2.035. Repeated process a few times to confirm.

Does this number sound correct? And what should I do with it? My virgin Winchester brass measures around 2.007. Should I just let the brass grow and keep it trimmed to 2.025, .010 under? I would like to have as much brass as possible to hold the bullet.

 

[Gene Poole]

Re: So I built this simple tool...

I checked mine with a sinclair gauge and was surprised at how deep it was. I've since seen several post on this and they all seem very deep. You're are below the norm best I can tell. 2.045 seems the norm from the threads I've been reading. Here was my results for 3 rifles:



I don't know what to do at this point. I still trim to 2.010 just to be consistent, but I often wonder if it matters. I may try just loading a box without bothering to trim and see how it goes.

 

[RotARy15]

Re: So I built this simple tool...

Interesting that it is that much shorter. Although I expected it to be about 2.020 simply because the books say to trim to 1.005 and the max is 1.015. Did not see 2.035 coming.

I'm trying to get more brass to hold the bullet because I'm also having some other problems.

I got a Lee Collet Neck Die, did all the finishing craftsmanship that the factory neglects to do and set it up only to find that the die doesn't have enough threading to allow it far enough into the Hornady AP press. Played with lock rings and found that Redding lock rings gave me the most space but not enough. The lock ring is as far up the die as it can go and the die is as far down as possible.

With that setup I could get enough neck tension to hold a bullet but not enough tension to successfully jam a round in the lands. So I spent the last 30 minutes flat sanding the lock ring to get more room to play with.

I was successful in getting more tension so I may continue the sanding to get even further.

 

[armorpl8chikn]

Re: So I built this simple tool...

Congrats. You have done well in being innovative. I have done this little trick ever since I lost my set of Sinclair guages. This method works just as good.
Of course you let your brass grow. The whole purpose of performing this trick is to let it grow.

Throw that Lee collet die in the garbage and use a good FL sizing die. If you set a FL die up correctly you will never need anything else, and your ammo will be just as good if not better than all these neck sizing guru's ammo. Not to mention your brass will last just as long. Trust me. I didn't just start handloading in 2008.
If you need pointers on setting up a die dig back through my posts or PM me, I will be happy to walk you through it step by step.

 

[RotARy15]

Re: So I built this simple tool...

I considered it, but I already have the collet die, a Redding body die, and a Forster Ultra seater die. Would rather not replace new equipment yet.

I was successful in getting enough neck tension. By sanding the lock ring thinner.

I will allow the brass to grow to no more than 2.025. I have no idea how many firings that will take but at least I don't have to trim anything for a while.

 

[crewchef]

Re: So I built this simple tool...

It took me 3 firings before my new Winchester brass got close for a rifle with chamber that measured 2.027 (custom barrel). Only a few pieces were over 2.017 but there was a pretty big range in total length at that point so gave me a chance to even it all out. I went .015 under trimming to 2.012. As I understand the SAMMI spec, the minimum chamber length is 2.025. If that's correct then book value is giving you .020 clearance at trimmed length and .010 at max length. Essentially I'm splitting the difference and will just plan to trim every firing so I don't get closer than .010.

Edit to add;

Very innovative thinking on the tool, seems to do the job and price was right!

As to the Lee Collet, I use the exact same set up, body die, Lee Collet and Forster seating. I think it's working the necks a lot less than what FL die was. I've got an SD of 8 on current load and I think the collet die and consistent neck tension are helping to get that number.

 

[armorpl8chikn]

Re: So I built this simple tool...

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Crewchef</div><div class="ubbcode-body">

As to the Lee Collet, I use the exact same set up, body die, Lee Collet and Forster seating. I think it's working the necks a lot less than what FL die was. I've got an SD of 8 on current load and I think the collet die and consistent neck tension are helping to get that number. </div></div>

How did you come to these conclusions? I use a FL Redding die on my 30-06 custom rifle and it turns out SDs in the single digits right down to a low of 3.7 like a machine with almost any load, even the ones that don't shoot great. Guys that have seen my rifle spit these numbers out are in shock. I don't weigh, uniform, or clean my primer pockets. I don't put them on a concentricity guage either. I do anneal after 3rd or 4th firing.
This is the reason a lot of new guys are buying dies they really don't need. They hear this kind of stuff and think it must be true and go and get 3 or 4 different dies for their tactical rifle. Very entertaining to a guy like me, but ultimately quite sad that people spend good money buying equipment that they don't need. If your load density and powder choice are correct for the bullet weight neck tension is background noise. You either have enough or not enough neck tension. If you use a FL die you will always have enough and in my vast experience that is all that matters if you use the right powder for the cartridge and bullet.

 

[crewchef]

Re: So I built this simple tool...

Just for clarity, my focus is F-T/R mid and long range so not really tactical if that makes a difference. My original purchase was Forster two die set w/ micrometer competition seating and FL sizing.

My conclusion on necks being overworked came from measuring. I removed the decapping/sizing ball rod and measured neck size before and after being sized. The FL sizing die was sizing neck down to .330 compared to collet which sized to .336. Starting measurement .344 so FL die worked the neck approximately 75% more than collet die. This with FL die set up to only bump shoulder .001.

I like the fact that neck is being squeezed down on a centered mandrel too.

As to buying equipment they don't need I would point out that purchased individually, the collet, body sizing and seater dies cost pretty much the same as any good two die set. And I certainly agree, dies aren't going to make a bad load good. The right tools used correctly might make a good load better though.

 

[RotARy15]

Re: So I built this simple tool...

On another note, I will take the liberty of hijacking my own thread and ask a question that has probably been asked before.

What is the best way to start building a load? This is my first time loading to such precision and I want to take everything that I can into account this time.

I've never messed with touching the lands before and would like to know where I should start.

I figured I would start jammed .010, run through the powder charges and then mess with seating depth. However, I'm debating whether being jammed is worth it. I do a lot of chambering and un-chambering and don't like to leave bullets behind.

If I start with the bullet touching the lands, do I have to be super precise? If the pressure difference between jump and jam is that big, would it be problematic if one round happened to be .001 jammed when it should have been .000? Am I worrying about the numbers too much?

I don't want my face to be all blowed up.

 

[SVG308]

Re: So I built this simple tool...

I always test my loads with a .015 or .020 jump. I realize pressure could spike if running max loads, but I don't typically load hot enough to where that would be an issue.

 

[Trevor300wsm]

Re: So I built this simple tool...

I started out with the Neck die, Body die, blah blah blah. I switched over to a FL Type S bushing die with a carbide size button. I'm loading for 3 different rifles (all the same caliber) and I'm getting ES's in the 10-14fps range (15 shot string) and SD's in the single digits, usually below 7fps. I can achieve these numbers even with NEW virgin brass. I FL size everytime now and run a .289 neck bushing giving me .003" neck tension. I don't turn necks, I don't use a concentricity gauge, I don't check for runout, I don't sort brass, I don't sort bullets. I shot a 5 shot group today out of a brand new rifle, out of a brand new barrel (unfired), new virgin brass, off a bipod and bag prone and it was just under .025". So, I'd say it's already accurate and will only get better with fire formed brass and a few more rounds down the pipe.

You can go about things the hard way, or you can listen to people who already know. It's really your choice, but I prefer to work smart, not hard. You don't have to go through a 12 step process to load "Precison ammunition". If your not shooting bench rest, then why go through the added effort for no return, atleast not any return that your actually going to be able to shoot good enough to see.

 

[armorpl8chikn]

Re: So I built this simple tool...

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">What is the best way to start building a load? This is my first time loading to such precision and I want to take everything that I can into account this time.
</div></div>
Start with good brass. Lapua and Nosler are great, Winchester is tops along with Lake City if available. In my opinion most evrything else is pretty much plinking brass. Hornady is one I have little experience with.

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body"> I've never messed with touching the lands before and would like to know where I should start</div></div>
Unless you are working with a bullet that responds well to being jammed leave it alone. There is often little to be gained besides a headache. You may need to jam Berger VLDs to make them hum, I have heard they also respond well to a large jump. Sierras and similar designs respond well to a .010"-.020" jump in everything I have shot them.

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body"> I figured I would start jammed .010, run through the powder charges and then mess with seating depth. However, I'm debating whether being jammed is worth it. I do a lot of chambering and un-chambering and don't like to leave bullets behind.

</div></div>
You already have it figured out. The worst thing that can happen is you need to unchamber a round and scatter your powder charge in your action. If you have custom guns like mine unless you have some compressed air and a bunch of tools with you your day may be done. It is a headache you don't need and you will gain nothing over actually developing a proper load with teh correct powder matched to the correct bullet.

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body"> If I start with the bullet touching the lands, do I have to be super precise? If the pressure difference between jump and jam is that big, would it be problematic if one round happened to be .001 jammed when it should have been .000? Am I worrying about the numbers too much?

</div></div>
No. Within a couple thou is fine. If you decide to load them .015" off the lands a couple thou either way won't matter much either. Most folks get really caught up on being exact to the extreme on this measurement....its hilarious.
Yes you are worried about the numbers too much.

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body"> I don't want my face to be all blowed up. </div></div>

You aren't going to blow your face off...unless you decide to go right to max loads in a manual with a heavily jammed bullet. Even then, you will probably only get the shit scared out of you. Its pretty safe unless you do something really stupid.

You have to keep everything in perspective and understand what is reasonable accuracy to expect from the rig you are shooting. Some idiots will burn a barrel out looking for something they can never attain.

 

[RotARy15]

Re: So I built this simple tool...

Cool, thanks for the help.

 

[crewchef]

Re: So I built this simple tool...

Won't offer opinion on jump or jammed but would recommend that you don't try to seat close to either side. Jam or jump them minimum of .015. If you're considering a jammed load then start with that when your working it up. You can always seat the jammed load deeper to make it jump without issue. If you have a hot load that's jumping and you decided to seat it longer and jam it you'll probably have pressure issues.