230 gn (#2251) Sierra seating problems

[Captain mf]

Just started looking at loading #2251 for 300 blk. 
first problem is my Redding seating dies will not adjust down to the 2.23” OAL recommended by Sierra. anybody else had this problem.

 

[ray]

Are you sure that the 2251 is suitable for this application?

From memory they are in region of 1.75" long, that wouldnt leave much room for powder, they need an 8 twist at 308 velocities  2500ish fps to maximise their potential.

[Andrew]

On 12/23/2019 at 12:22 PM, ray said:

Are you sure that the 2251 is suitable for this application?

From memory they are in region of 1.75" long, that wouldnt leave much room for powder, they need an 8 twist at 308 velocities  2500ish fps to maximise their potential.

The 300AC Blackout is designed to shoot 240 grain, 30 caliber bullets at sub-sonic velocities. They will stabilize the 230 MK with 8" or faster twist. My 300's are all 1:7" twist which is about standard.~Andrew

[Andrew]

As to the seating problem? How close are you to the 2.230"? Is the die as low as it can be towards the shell holder? Are you using a redding shell holder as well as the die?~Andrew

 

[ray]

The reason these wont seat to 2.230 is due to the shape of the nose.

You are trying to seat a bullet that has 0.975" nose to a coal that would have 0.100" of its nose inside the case neck.

These 2251s really cant be compared to the old 240smk which has a much shorter nose and overall length.

[Andrew]

I was talking about stability, and addressing the mechanical inability to get them to Sierra's specified depth. I have never shot them, preferring the Nosler 210's but it begs the question as to why Sierra lists data for them at that seating depth.~Andrew

[Captain mf]

Thanks for the responses 

I am using a lee no 4 shell holder, and have backed off the Redding die 3/4 - 1 turn (0.05-0.07”) from touching the shell holder , with the seating screw fully down this gives me cartridge length of 2.2515.  So 0.0215” longer than the Sierra data sheet.  Thinking about this I will try screwing in the die until I feel the crimp set in and this may give me the the depth on the chart.  Although I prefer to start off using the manufactures data I do use quick load which predicts chamber pressure. But the reason for my caution is that the top end loads on the Sierra data sheet flag up as in the danger area “Do not use” 

to answer question asked I have 7.5 twist rate and using lil’ gun. 
sierra data ranges from 8.3 - 13.5 gn @ 2.230”. 
using quick load I am looking at starting my load at 9.5gn @ 2.252” (having measured my max coal For this head with a hornady gauge)

 

[Andrew]

What rifle? ~Andrew

[Captain mf]

Schultz and Larsen legacy 

[Andrew]

I would seat them the best I could and run with it provided they fit in the magazine. Nice rifle.~Andrew

[KABOOM]

On 12/23/2019 at 10:32 AM, Captain mf said:

Just started looking at loading #2251 for 300 blk. 
first problem is my Redding seating dies will not adjust down to the 2.23” OAL recommended by Sierra. anybody else had this problem.

 

I would contact Redding for advice, failing that new die set RCBS or FORSTER

 

[Captain mf]

Cheers but I did sort it by winding down the die until I found where the crimping action actually took place, then backed off a little bit by bit to avoid the crimp  and they just managed to get the depth I was after. Although first go at 200 yards was not brilliant but then I did reduce the load quite a bit from the serria data. Which compared with quick load seemed very high. Def needs a lot of development which for me is the interesting bit. To be honest I don’t have practical reason for doing apart from the fun of sorting it out. Not that I’ll being do that for a while now With our  crono problem  cheers