123gr FMJ and 125/150 gr Soft Point Seating Depth and Powder Weight in 7.62X39 Bolt

[ljones]

Okay so new in reloading. I want to load up some 123 gr FMJ for plinking and both 125 gr and 150 gr soft point .311 dia Sierra Pro Hunters for hunting deer in a Howa Mini Bolt 7.62X39. Where would those experienced suggest I start for seating depth with those 3 bullets for best accuracy? I will of course be using start data and working up for powder just wanted a suggestion based on others experience as what they found best for seating depth for those 3 bullets.

 

[nrut]

Start at mag. length..
If the round chambers you are good to go..
If not seat deeper until the round chambers..

 

[mbogo3]

The Hornady #6th Edition lists the 150gr bullet at 2.2" OAL /for powder either IMR4198 or the Hodgon version.That's what i feed my CZ527 same for 123gr bullets.[2.19" OAL] In mine switching to mag primers cut groups in half....One round per customer........deer

 

[ljones]

The Hornady #6th Edition lists the 150gr bullet at 2.2" OAL /for powder either IMR4198 or the Hodgon version.That's what i feed my CZ527 same for 123gr bullets.[2.19" OAL] In mine switching to mag primers cut groups in half....One round per customer........deer

Yeah just measured my chamber with 3 different bullets to the lands and I couldn't get anywhere close to the lands due to the mag length. Big jump to the lands. Was able to get the closest with the 150gr. What are your start and finish gr weight with the IMR 4198 with the 123FMJ? The various manuals have start weights from 22-24 grains and top weights from 24-26.5 which has ne scratching my head as to where to start in the Howa.

 

[LawrenceN]

My Lyman Reloading manual (49th. edition), doesn't have 125 gr. in the list but it shows 22.0-24.6 gr. of IMR4198 for the 123 gr. bullets and a COL of 2.200. I'm expecting a Howa rifle next week that I will have to start developing loads for so we'll be in much the same boat. I have a lot of reloads from my old SKS hunter that didn't give me the accuracy I wanted, so they'll be tried out in my Howa. I don't have any 150 gr. bullets, but I do have 123 gr. Hornady Interlocks and some SST's as well. The 123 gr. has been good deer medicine thus far. The best performing powder for me has been Reloader 7, but as I'd mentioned that was out of my SKS and it gave me 1-7/8" groups at 100 yds. For the Howa, I'll be starting from scratch. As to seating depth, this is what I did with my Swedish mauser and what I will do with the Howa after I get it. I took a prepped case, lightly seated a bullet, lubed the chamber throat and the bullet, and gently closed the bolt. Then I carefully extracted the round and measured the COL. I then inserted it into the mag to see if it would seat and feed reliably into the rifle. If it didn't, I kept seating the bullet a little deeper until I achieved the desired balance between COL and mag seating and feeding. Measuring the difference told me how much "jump" I'd get when shooting the reloads. Good luck to you and let me know how your reloads work out.

 

[ljones]

I use the Hornady Lock-N-Load Overall length gauge and the modified cases to measure mine with the different bullets. I did find an article where the writer used CFE BLK powder in his Howa and was able to find a load fr both the 125 and 150gr Sierra Pro hunters that were less than an inch 5 shot groups so will be using that powder to try in mine. I will use magnum primers and see if that helps group size in mine. For the plinking rounds going with Dominion primers and D4198 powder from Canada Ammo to keep costs as low as possible and see what accuracy I can get but for plinking I am not worried about clover leaf groups. We will see what happens. Got to work up a load in my Tikka T3 Hunter first in .30-06 for spring bear if my health allows me to get out for them.

 

[mbogo3]

I'm getting.627" 3 shot groups at 100 yards using 25.5gr of H4198/123gr Hornady SP bullet .616" with the same bullet and 25gr of the same powder PPU brass and Fed mag primer. Sierra .311/150gr shot .923" with 29gr of H335/Fed mag primer The mag primers before I take flack cut the groups nearly in half so I use them.This is out of a CZ 527 carbine with several big bodied AB wt's to it's credit.

 

[ljones]

I'm getting.627" 3 shot groups at 100 yards using 25.5gr of H4198/123gr Hornady SP bullet .616" with the same bullet and 25gr of the same powder PPU brass and Fed mag primer. Sierra .311/150gr shot .923" with 29gr of H335/Fed mag primer The mag primers before I take flack cut the groups nearly in half so I use them.This is out of a CZ 527 carbine with several big bodied AB wt's to it's credit.

I believe I had read your comment in another thread about using the magnum primers in the 7.62X39 and thus wanted to try them with my hunting loads and see the results.