Primer testing W/ 90 gr. Sierra in a 223

[Bob3700]

Started testing different batches of SRP in a 223 bolt gun (30 inch bbl) behind 90 gr. Sierra bullets.
Powder was VV 135 and primers tested were Wolfs, CCI 41s, CCI BR-4s, CCI 450s. Same case prep. Peterson Cases weigh sorted, necks run over a mandrel after FL sizing.
Fired 20 shot strings with each type of primer. There was virtually no difference in SD between all the primer types. All exhibited SDs in the 12-14 fps bracket. Wolf was actually the lowest SD of them all. That said, u couldn’t shoot the difference between them.
Am going to shoot the same ammo/ primer test next Saturday to see if the results repeat themselves.
Bob

 

[Bat Rastard]

Peterson makes 223 brass?

 

[SeabeeKen]

Peterson makes 223 brass?

Not that i have seen and isnt on their website under match brass

 

[fkimble@charter.net]

And VV135 is kinda fast for a 90grainer ?

Frank

 

[1varmint]

Try some federal primers too

 

[Bob3700]

My bad, the brass was Starline. The VV135 gave a muzzle vel. of 2825 from a 30 inch bbl.

 

[kyotekiller25]

Curious what your ES were?

 

[Jeff Porter]

Bob- I am trying out N135 in Starline 5.56 brass 450 primer and a 90 JLK bullet in an 30” Palma barrel and getting 2820 with 24.1 gr. SD and ES vary with seating depth deeper seated single digit SD and ES low teens, seated closer to touch they group better but ES and SD are higher. SD low teens ES near 30. Guessing that is related to neck tension being more uniform when more bearing surface is in the neck. Might improve it with a smaller neck bushing.

 

[Bob3700]

Jeff,
Current bullet seating is “ soft seating” , 0 + .025” long.
Load shoots small at 600 yds.
Have been using the “ soft seating” method across many calibers ( 308; BRX, 6XC) with good success on the target. Perhaps I am just old school n resistant to change but I have been letting the target tell me what it likes.
It does take a bit to refine ur brass for the correct light neck tension.
Will have to try increasing the tension to see if the groups stay small while reducing the SD.
Bob

 

[Bronsin]

Are you weight sorting primers? And seating them .008 deep?

 

[Bob3700]

Are you weight sorting primers? And seating them .008 deep?

No! I have weight sorted primers and while I feel it can’t hurt, shooting with irons n a sling I don’t think I can shoot the difference.
If u feel that a few thou difference in primer seating depth is a critical factor at 1000 yds by all means put ur efforts there.
The amount of atmosphere between u and the target, to me, will negate a small difference in primer seating depth. That said, if u think it makes a difference, it does.

 

[Bronsin]

No!

Hence the results...........

 

[Bronsin]

You posted chronograph results, not 1000yd targets.

 

[Jeff Porter]

I shot my .223 with the 90’s at 1000 today at Atterbury in 12-15 mph winds. 20 shot SD was 13 with the N135 / 450 primers new 5.56 Starline brass.

The fun started in the third relay when I was shooting the .308 with 155.5’s and the wind went up to 20 mph with gusts, let offs and switches. Ended up with 15 moa on the gun when I came off the line.

I have never been happier to shoot a crappy score. That as really kind of fun in a masochistic way.

 

[Bob3700]

Jeff,
With that level of wind n switches, ur lucky to stay on the target!
I have shot the Berger 155.5 s and they are the best bullet in their wt. class. U might have been surprised at how the 90s would have handled that wind. They are closer to the 185 Jugs than the 155.5s.
Going to try n get to Atterbury the weekend of May18. A friend lives in Indy and he wants to get back into competitive shooting. Figured I would give Atterbury a try as I have not shot there.
Bob

 

[Cfshooter]

I’ve conducted a similar test a few weeks ago, but from an AR. Not much difference on target but can see a slight difference on chrono.

 

[Jeff Porter]

Jeff,
With that level of wind n switches, ur lucky to stay on the target!
I have shot the Berger 155.5 s and they are the best bullet in their wt. class. U might have been surprised at how the 90s would have handled that wind. They are closer to the 185 Jugs than the 155.5s.
Going to try n get to Atterbury the weekend of May18. A friend lives in Indy and he wants to get back into competitive shooting. Figured I would give Atterbury a try as I have not shot there.
Bob

Bob - I did shoot the 90’s as well as the .308 yesterday. First two strings were with 90’s in any any and yes they were much better in the wind than the .308.

Winds started the day 10-15 at 2:00-2:30 with let ups. No mirage at all visible on the range. By the third relay it was up to 17-20 almost full value. I came off the second relay with 7 minutes on the 90’s. I put 8 on the .308 just to see where it would hit. My scorer says “you need 10 minutes right or two left and aim at the target to your right. “

Second sighter was a 6 at 3:00 on my target. Third sighter was next to it. Took 3 moa off and third sighter was a mid ring 10. So I started with 15 moa right. Looking at the predictions for 20 mph at 2:30, that was pretty close to spot on.

155.5’s



90’s- I was so busy watching the flags I didn’t think to add a half moa up lol.

 

[bpm990d]

Bob- I am trying out N135 in Starline 5.56 brass 450 primer and a 90 JLK bullet in an 30” Palma barrel and getting 2820 with 24.1 gr. SD and ES vary with seating depth deeper seated single digit SD and ES low teens, seated closer to touch they group better but ES and SD are higher. SD low teens ES near 30. Guessing that is related to neck tension being more uniform when more bearing surface is in the neck. Might improve it with a smaller neck bushing.

Jeff what's the chamber in your rifle? Is it a 223 ISSF or a Gill or somthing else.

 

[Jeff Porter]

It is stamped as .223 FTR so a pretty long Freebore. I am not 100% certain what is is actually. I'll back calculate some numbers using the touch length seating depth of the 90's. I did this a while back and I think it was in the 0.200" range

 

[Jeff Porter]

Sorry for the Thread hijack Bob -

I ran the numbers for the conditions yesterday..

The .308 was spot on for a 20 mph wind at 2:30

MOA per MPH	0.82​	0.82​	0.82​	0.82​	0.82​
155.5 Fullbore
Wind speed	10​	12​	15​	17​	20​
12:00​	0.0​	0.0​	0.0​	0.0​	0.0​
12:30​	2.5​	3.0​	3.7​	4.2​	4.9​
1:00​	4.1​	4.9​	6.2​	7.0​	8.2​
1:30​	5.7​	6.9​	8.6​	9.8​	11.5​
2:00​	7.1​	8.6​	10.7​	12.1​	14.3​
2:30​	8.0​	9.5​	11.9​	13.5​	15.9​
3:00​	8.2​	9.8​	12.3​	13.9​	16.4​

The 90's in 12-15 at 1:30-2:00 came up to the 6-7 minutes I was using.

MOA per MPH	0.72​	0.72​	0.72​	0.72​	0.72​
90 VLD
Wind speed	10​	12​	15​	17​	20​
12:00​	0.0​	0.0​	0.0​	0.0​	0.0​
12:30​	2.2​	2.6​	3.2​	3.7​	4.3​
1:00​	3.6​	4.3​	5.4​	6.1​	7.2​
1:30​	5.0​	6.0​	7.6​	8.6​	10.1​
2:00​	6.3​	7.5​	9.4​	10.6​	12.5​
2:30​	7.0​	8.4​	10.5​	11.9​	14.0​
3:00​	7.2​	8.64​	10.8​	12.24​	14.4​