Seating Depth - What is min bullet in case?

[John Galt]

Seating Depth - What is min bullet in case? My competition bullet seater won't help me if they are seated so long that they can tip after the seating.

I have a new Ruger M77 Target .223 bolt action and am preparing to do my first hand loading for it. I'm way new to reloading. Redding Comp neck & Comp seating dies.

This will be my first load and used for plinking. My next load will be 50gr v-Max in different brass. I ordered Varget and Fed 205M.

I loosely put in the 55gr PSP "Varming Nightmare" bullet in a case and pressed it into the rifle's chamber. It seated the bullet only .110" into the case. Backing off .001 for a "jump" and .002 to allow for inconsistent bullets, would make .113" into the case. Not much!!!

The loading manual mentions "one caliber" into the case.

What's the minimum bullet into the case?
- Loading from fixed magazine for shooting squirrels and such.

*I measured the max brass length. SAAMI is from 1.75-1.76" My chamber is 1.792" I did this by cutting 1/2 the case neck off and putting in a bullet upside down and then putting the brass ring back on. Then chambering. I plan to change "trim to length" from 1.75 to 1.78" as the brass grows to help with these issues. Seems both my chamber and "freebore" are over long.

* I put a bullet in the brass upside down and loose and chambered and got 1.911" from base to lands.

 

[Art Eatman]

I load for a sporter 77 MK II in .223. So far, it doesn't seem picky, always giving 1/2 MOA 3-shot groups with any old load. Therefore, I just haven't worried a lot.

From a "tipping" standpoint, I'd just seat to maybe 0.125" and see if it's easy to loosen with my fingers. If so, go deeper. However, if care is taken in handling the ammo, it shouldn't be a problem.

You can also load three of each at different depths and check the group sizes...It might not be critical in your rifle.

Art

 

[Grump]

I'll need to mike some 55-gr FMJBTs, but that sounds like all the seating depth they have, between the channelure and where the boattail takes the jacket sub-caliber.

Based on some goofy things like that, I've always considered 1/2-caliber doable as long as the case necks are stiff. 1 caliber is the "rule of thumb."

 

[John Galt]

Thanks!

The bottom edge of the cannelure on the 55gr rounds I'm loading is just over .223" from the bottom of the bullet.

I'll load them .15" into the neck and then not trim the cases and hope they grow to engage .18" over time with the same OAL. I should maintain the same OAL over time to keep the same case capacity and not change the space for the load. After I find my best load, I'll also try varying the seating depth as well. Then, of course, go back and try a touch more and less powder again.

- All things considered, velocity, etc, what bullet wt do you guys shoot in your bolt action rifles? There's 40,50,55,60. I was planning to use 50grn v-Max and bought 500 of those.

- Any big difference between Hornady v-Max and Nosler to justify the extra cost of Nosler?

Art, good to hear about your accuracy. I will be happy with that! I havn't even fired it yet as I wanted to combine my first range trip with load developement and have been accumulating press, parts, powder, etc. I'm going out this weekend & will let you know what kind of 5 shot groups I end up with.

 

[Steve Smith]

The rule of thumb is one caliber's worth, but you don't have to follow that. If I were you I would give more than .001" as a "jump" and consider .005" to .010" safer.

Irregardless of all of this, follow Art's recommendation, as it should work well.