Short .223 Bolt Gun & N133

[Chauncymayne]

I've been searching pretty hard to see if there is load data out there for N133 & 75 ELD's (and 62 ELD-VT's) and for whatever I have not been able to find any. I know the 62 ELD-VT is a pretty new bullet but the 75's have been around for awhile. I have not been able to get my hands on 8208 or 4895. Ramshot Tac yielded some pretty huge spreads (ES's around 100 & SD's in the 40's) in Velocity but decent groups (around 1 MOA). I was able to get my hands on some VV N133 and tried to use some data I found with Benchmark powder to get started.

I will preface this with the fact that I am running an 18" - 7 Twist Proof Barrel chambered for the 75 ELD to be about .020 off the lands at 2.550 COAL.

I shot the 62 ELD-VT at a COAL of 2.517 (seated so the Boat-Tail sits at the Neck-Shoulder Junction)

5 Shot Groups

22.0 Gr. N133 AVG. Vel. - 2750 FPS (No Pressure)
22.5 Gr. " " - 2805 FPS (No Pressure)
23.0 Gr. " " - 2870 FPS (No Pressure)

None of these Yielded anything great, 22.5 gave me just inside a 1 MOA group. I chalked that up to possibly be jumping them way too far on account of my chamber being cut for the 75's.

The 75's yielded me some better results.

75 ELDM - COAL of 2.550 - 10 Round Groups

21.8 Gr. N133 AVG. Vel. - 2650 FPS (No Pressure)
22.0 " " - 2670 FPS (No Pressure)
22.2 " " - 2700 FPS (No Pressure - Best Group 3/4 MOA or better)
22.4 " " - 2730 FPS (No Pressure)

I am going to turn up the charge with the 75 ELD's to see where I find pressure and will update once I do.

All groups shot with N133 gave me what I consider to be acceptable SD's considering this cartridge and the purpose of the rifle.

If anyone has an experience with N133 and 75 ELDS in a Bolt Rifle any information would be appreciated.

 

[ballisticdaddy]

Not a lot of info for .223 Rem using N133 but was able to find this.....

 

[Chauncymayne]

Not a lot of info for .223 Rem using N133 but was able to find this.....

View attachment 8579366

I found that on the VV website as well. I was hoping to find some information more geared toward a 223 chamber with the longer freebore.

 

[ma smith]

AFAIK, the 4895 or 8208 or ARComp etc. powders (commonly used for .223 heavies) are just slightly faster than 140/Varget.

VV equivalent for 1 step faster than VV140 probably VV 135 not VV 133, se ...

Try this handloading powder also with .223 Remington loads with a bullet weight of 3,9-4,5 grams (60-69 grains) and you will be surprised of the accuracy and velocity performance of the combination.

source>https://www.vihtavuori.com/powder/n135-rifle-powder/

 

[Chauncymayne]

I have already looked extensively through VV website and had also found data on a sierra site for 69 Gr. SMK's with N133.

Most of the load data on those sites are for chambers with very short freebore. Hoping to get some feedback from anyone who has personally used N133 in a bolt gun 223 with a wylde chamber or longer.

 

[Chauncymayne]

Just to Update this Thread with my Findings....

I am going to stick with the 22.2 grains of N133 under a 75 ELD-M at a COAL of 2.550.

*STARLINE BRASS*

I did run this up to 23.0 grains of powder, but did start to notice things become more inconsistent and some pressure signs began to show. Had a buddy run this in "Gordons" to see what that program gave as far as feedback... Based on what the program gave back, the predicted velocity matched my actual velocity within 5 FPS at 22.4 grains of powder. It also did say I was around 62k PSI at that charge, although I did not have any issues at or above 22.4 grains in the current winter climate in Southeast PA, I am sure that could change with some summer temperatures.