Bullet Seating Depth?

[mdslammer]

Note: I'm a newbie for reloading.

Still tweaking my load for my .308 Win. I've narrowed
my powder amount to 43.8gr. & 44.gr. of Varget.

Using Hornady 178gr. A-MAX bullet, Winchester Primers and once fired Federal Brass.

I was going to start seating the bullet .005" off the lands and
then .007", .009" and finally .0010".

Is it recommended to seat any deeper than .0010" or not?

Thanks.

Mark

 

[Helmet]

Re: Bullet Seating Depth?

They shot very well for me at .010" off the lands. Some of my best groups ever.

 

[mdslammer]

Re: Bullet Seating Depth?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: ArmchairElite</div><div class="ubbcode-body">They shot very well for me at .010" off the lands. Some of my best groups ever. </div></div>

Good to know. Thanks for the reply.

 

[boltgunluvr]

Re: Bullet Seating Depth?

Assuming you're NOT using a factory mag?

 

[armorpl8chikn]

Re: Bullet Seating Depth?

You are tilting at windmills. You are gonna shoot your barrel out looking for something you probably think needs discovery.
Some of my best groups are .015" off the lands and some are as much as .100".

Lemme guess. You have a factory Remington 5r.

Get some 175SMK bullets and load them with a healthy dose of Re15 or Varget at mag length and see if things don't work out just fine for a tactical rifle.
If however you are trying to break into BR VFS then maybe you should play around with some bullets real close to the lands.

I know you want the most accurate ammo you can get but you may be searching in vain. Why did you get a repeater if you plan to single load every round. Find a load to shoot as the gun was designed.

 

[mdslammer]

Re: Bullet Seating Depth?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: armorpl8chikn</div><div class="ubbcode-body">You are tilting at windmills. You are gonna shoot your barrel out looking for something you probably think needs discovery.
Some of my best groups are .015" off the lands and some are as much as .100".

Lemme guess. You have a factory Remington 5r.

Get some 175SMK bullets and load them with a healthy dose of Re15 or Varget at mag length and see if things don't work out just fine for a tactical rifle.
If however you are trying to break into BR VFS then maybe you should play around with some bullets real close to the lands.

I know you want the most accurate ammo you can get but you may be searching in vain. Why did you get a repeater if you plan to single load every round. Find a load to shoot as the gun was designed. </div></div>

Sorry, but I don't understand your comment <span style="font-style: italic">You are tilting at windmills. You are gonna shoot your barrel out looking for something you probably think needs discovery.</span>

Second, I'm using a 178gr. A-MAX bullet so I'm looking for advice for
those who've reloaded using this specific grain bullet.

Maybe you can educate me as to what BR VFS means. Sorry, new to reloading.

Finally, my rifle is a bolt action .308. I don't have a repeater.
And, I am trying to find a load that works best for my rifle. That's
why I posted this question.

 

[Deadshot2]

Re: Bullet Seating Depth?

Every barrel has a finite life for ultimate accuracy. While in search of that "magic load" that allows you to shoot "bug holes" at 100 yards, shooters often shoot out that life and end up with just a barrel of "average accuracy".

As for "repeater", even though it's a bolt action, if it has the ability to load from a magazine (even if you have to push rounds through the top of the receiver to fill it, it's considered a repeater.

As for OAL, I've learned somewhat the hard way that "magazine length" rounds can be just as accurate as those that are loaded way to long for the magazine box.

My Rem 700 5-R shoots nice tight groups at pretty much all ranges when loaded to lengths that feed freely from the magazine. I figure that there may come a day when having the ability to merely cycle the bolt and shoot again will be more important than having a pocket full of cartridges that I have to insert by hand after every shot.

 

[AtOne]

Re: Bullet Seating Depth?

Here's an interesting read for you from Berger
Berger tips but can be applied to other bullets as well.

Every rifle is different so the best thing to do is to find what yours likes and go with it.

As for shooting out your barrel finding the perfect load...Have fun with your load development and don't worry about it.

I enjoy the load development part of shooting and I'm sure you'll learn a bunch along the way.

Good luck

 

[mdslammer]

Re: Bullet Seating Depth?

Thanks guys for the info and links. It's all new to me and a
learning process I look forward to.

Best.

Mark

 

[ricklaut]

Re: Bullet Seating Depth?

Mark - saw your post here locally on NS and I was gonna reply there - but I was going to point you back here with a link anyway. I went through this last year. So here goes...

If you haven't already, take a look at this link. It helped me tons... What I did different was used a "poor mans" method of finding the lands (basically as rat907 at NS said - except I did that multiple times to make sure it was repeatable and accurate). I ended up finding that my .308 shot best when right at the lands. Every time I get a new box of bullets, I go through the same exercise to make sure they're seated at the right spot, since ogive changes from lot to lot (hence COAL isn't a reliable number).

To me, the most important part of the info in that link is at the very end. Pay particular attention to the paragraph towards the end - <span style="font-style: italic">"However it is IMPERATIVE you understand the following. On occasion the rifle will prefer a different bullet/rifling relation. Perhaps it be .015” jammed, or .030” out of the rifling totally or .030” “jump.” But START ALL LOAD WORK JAMMED! This is because in the next chapter we are going to learn what actual MAX load for this rifle is with a given powder and this bullet. Being jammed into the riflings increases pressure!".</span> Know that this step is occurring BEFORE working the load up, for the above reason.

I can't argue with the success I've had using this method.

 

[mdslammer]

Re: Bullet Seating Depth?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: ricklaut</div><div class="ubbcode-body">Mark - saw your post here locally on NS and I was gonna reply there - but I was going to point you back here with a link anyway. I went through this last year. So here goes...

If you haven't already, take a look at this link. It helped me tons... What I did different was used a "poor mans" method of finding the lands (basically as rat907 at NS said - except I did that multiple times to make sure it was repeatable and accurate). I ended up finding that my .308 shot best when right at the lands. Every time I get a new box of bullets, I go through the same exercise to make sure they're seated at the right spot, since ogive changes from lot to lot (hence COAL isn't a reliable number).

To me, the most important part of the info in that link is at the very end. Pay particular attention to the paragraph towards the end - <span style="font-style: italic">"However it is IMPERATIVE you understand the following. On occasion the rifle will prefer a different bullet/rifling relation. Perhaps it be .015” jammed, or .030” out of the rifling totally or .030” “jump.” But START ALL LOAD WORK JAMMED! This is because in the next chapter we are going to learn what actual MAX load for this rifle is with a given powder and this bullet. Being jammed into the riflings increases pressure!".</span> Know that this step is occurring BEFORE working the load up, for the above reason.

I can't argue with the success I've had using this method.

</div></div>

Thanks Rick for taking time to help me out. Good info and I'll
check out the link as well.

So you didn't have a pressure issue with seating the bullet right at
the lands huh? Good to know. I've been warned about having too much
pressure build up and was a little hesistant to seat right up to the
lands.

I'm going to recheck my O.A.L. tomorrow with the Hornady O.A.L. tool
just to verify.

If there is a pressure issue what can I look for? I heard a flattened
primer or case crack/wear would be an indicator. Anything else to be
aware of?

Thanks again.

Mark

 

[Helmet]

Re: Bullet Seating Depth?

If the bolt starts getting harder to lift you should back off some. Ejector marks on the brass also mean you need to back off some.

 

[mdslammer]

Re: Bullet Seating Depth?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: ArmchairElite</div><div class="ubbcode-body">If the bolt starts getting harder to lift you should back off some. Ejector marks on the brass also mean you need to back off some. </div></div>

Good to know and thanks.

 

[ricklaut]

Re: Bullet Seating Depth?

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

So you didn't have a pressure issue with seating the bullet right at
the lands huh? Good to know. I've been warned about having too much
pressure build up and was a little hesistant to seat right up to the
lands.
</div></div>

No problem, Mark.

I haven't had a pressure issue because I started developing the load at the lands. Let's say I'd already found my "optimal" load, and let's say it was seated somewhere off the lands. Using that same amount of powder and seating at the lands WILL raise the pressure. Remember, that article presupposes that you haven't gone on to finding your "max" load for the rifle yet.

Edited to add from the quoted post: <span style="font-style: italic">"But so long as you START JAMMED and work towards JUMP your safe as can be. NEVER start jumping and move towards jammed when near or at MAX loads, no,no, no."</span> That says it better than I did.

Pressure signs... many have already covered them. Hard bolt lift, flattened primer, ejector marks imprinted on the brass, primer blowout, smeared headstamp. I think flattened primers are the least reliable sign. I start paying attention if I get that, and (for example ejector) marks.