Sierra Accuracy Load for 223 90 grain SMK

[chkunz]

I would appreciate someone supplying me with the accuracy load from the Sierra manual for the 223 90 grain SMK. My manual is several years old and pre dates this bullet. I sent Sierra an email asking for the info but have not received a reply yet. Thanks.

 

[bigedp51]

Googled subject and this is the best I can find.

Handloading The .223 Remington For The AR15
http://www.shootingtimes.com/ammo/ammunition_st223_120606/

Requesting load data for 223 Rem - 90gr SMK
http://forum.accurateshooter.com/index.php?topic=3749371.0

I also remember someone saying to use a Powley Computer. :

 

[chkunz]

Googled subject and this is the best I can find.

Handloading The .223 Remington For The AR15
http://www.shootingtimes.com/ammo/ammunition_st223_120606/

Requesting load data for 223 Rem - 90gr SMK
http://forum.accurateshooter.com/index.php?topic=3749371.0

I also remember someone saying to use a Powley Computer. :

Thanks, one reference is for the AR and I am interested in the Sierra load since it will probably be for a bolt gun. I have the Powley Computer in hand and will see what it says but I have had good experience with the Sierra manual accuracy loads. I may have to buy a new manual to get the one page. I sent Sierra an email a couple of days ago so maybe they will reply.

 

[chkunz]

I received the response from Sierra, so now I have my answer.
thanks to all.

 

[chkunz]

I would like to be sure I give a big thank you to Sierra and be sure that I did not imply that they were not responsive. I received a timely personal message and a follow up. It seems like in this day and time we expect instant response to our request. I have had a great relationship with Sierra for many years and they have always been great to deal with. I have had great experience with their accuracy load data. Thank you Sierra!

 

[bigedp51]

I received the response from Sierra, so now I have my answer.
thanks to all.

There is a phrase called "sharing information", so what information did Sierra give you? My Sierra manual is just as old as yours and has the same "blank page". :

Both gstaylorg and I are tied with the same response time of 12:52, beautiful minds think alike.

 

[chkunz]

They were nice enough to sent me a copy of the complete page from the current manual that lists the 90 SMK. The accuracy load is 22.4 grains of IMR 4064 and a MV of 2600 fps. If I were sharp enough with the PC I would request permission to copy and paste the complete page here but that is beyond my skills. Just out of curiosity since the accuracy load turns out to be an IMR powder I am going to check it out on the Powley Computer and if I can get something that looks reasonable I will post that here. I am trying to figure out if it is feasible for the 223 with the 90 grain SMK to be competitive with the 308 for F T/R.

 

[bigedp51]

Let your fingers do the walking....................

tran·scribe
put (thoughts, speech, or data) into written or printed form, or write or type out full sentences.

stingy
mean, miserly, close-fisted, penny-pinching, Scroogelike, commie pinko pervert.

subtle hints
not immediately obvious or comprehensible, delicately suggestive; not grossly obvious: a subtle hint

 

[Snuggie]

T-Rex, what twist barrel do you have? I'm interested in using the 90's over the 80's also. Thanks, Snuggie. 8)

 

[chkunz]

The 90 SMK will get you closer to .308 performance than one of the 80-somethings. IIRC, there might possibly be some issues pushing those too fast, as in jacket failure or something like that. My recollection is that some folks were pushing them in the 2700-2750 fps range for that reason, but it's been a while so don't hold me to that. In any event, the BC of the SMK 90 is comparable to some of the Berger 30 cal bullets in the 155/168/175 gr range, but slightly behind the 90 VLD or 185 Juggernaut. If you can get them moving reliably a little faster than 2700-2750 fps, you should be able to get performance on par with a .308 shooting 155s/168s/175s. However, you will be at a slight disadvantage in terms of windage as compared to 185s or heavier in a .308. My take is that you should be able to them working, so shoot away and don't worry about it. They should do just fine for F-TR matches, particularly from 300-600 yd (MR).

This gets a little long and twisted but here is what I am thinking. I am a sling shooter, I get to shoot the big target. I have been shooting the AR in the any/any category at 600 yards with the 75 A Max and 80 grain SMK bullets and that combination is easy and fun to shoot. I have a tube gun in 260 Remington that I shoot 1000 yards with and it shoots really well but it is a real gun shooting real bullets (recoil) and not as much fun to shoot. So I am thinking about a nice tube gun set up to shoot the 90 SMK at 600, probably will perform better than the AR and still fun to shoot with low recoil. So I am looking at the ballistics and wind drift of the 90 SMK and it looks favorable. In fact the more I look at it I am wondering why the F T/R folks are shooting the 308 at 600 or 1000 yards; it appears to me that the 223 with the 90 SMK is the better choice. Then I remember seeing the 223 push out the 30 cal in the National Match Course (NMC aka XTC) and wondering if that is where F T/R is headed. Less recoil is always more conducive to the performance of the shooter and this is probably an under rated factor.

 

[chkunz]

T-Rex, what twist barrel do you have? I'm interested in using the 90's over the 80's also. Thanks, Snuggie. 8)

I do not have a gun yet set up for the 90s. I am just doing research and considering if that would be a good option for me. See my last reply above. But Sierra says 6.5 twist and the gun would probably need a chamber specifically designed for this bullet.

 

[chkunz]

Let your fingers do the walking....................

tran·scribe
put (thoughts, speech, or data) into written or printed form, or write or type out full sentences.

stingy
mean, miserly, close-fisted, penny-pinching, Scroogelike, commie pinko pervert.

subtle hints
not immediately obvious or comprehensible, delicately suggestive; not grossly obvious: a subtle hint

Maybe I should buy a copy of the latest version of the Sierra manual and send it to you. that way I would be respecting Sierra's copy rights.

 

[Snuggie]

T-Rex, what twist barrel do you have? I'm interested in using the 90's over the 80's also. Thanks, Snuggie. 8)

I do not have a gun yet set up for the 90s. I am just doing research and considering if that would be a good option for me. See my last reply above. But Sierra says 6.5 twist and the gun would probably need a chamber specifically designed for this bullet.

Thanks man. I have a 7.7 twist chambered for 80's. It's a laser! Have shot several 199's with it. Pointed the SMK's. Will try trimming then pointing to see what happens. Unfortunately I don't think my twist will stabilize the 90's. Just some input.

 

[bigedp51]

Maybe I should buy a copy of the latest version of the Sierra manual and send it to you. that way I would be respecting Sierra's copy rights.

You said something about respecting copyrights? Is that governed by percentage of what you copy and give away? :

The accuracy load is 22.4 grains of IMR 4064 and a MV of 2600 fps.

Never mind I'll do what you did and get it free from Sierra like you did.

Crafty
Skilled in or marked by underhandedness, deviousness, or deception.

 

[chkunz]

T-Rex, what twist barrel do you have? I'm interested in using the 90's over the 80's also. Thanks, Snuggie. 8)

I do not have a gun yet set up for the 90s. I am just doing research and considering if that would be a good option for me. See my last reply above. But Sierra says 6.5 twist and the gun would probably need a chamber specifically designed for this bullet.

Thanks man. I have a 7.7 twist chambered for 80's. It's a laser! Have shot several 199's with it. Pointed the SMK's. Will try trimming then pointing to see what happens. Unfortunately I don't think my twist will stabilize the 90's. Just some input.

If you are a sling shooter you get a big target and reading the wind is important and the 80 SMK or 75 A MAX are good to go right out of the box and as you say shoot like a laser. If you are F Class you get a small target and the little things matter but still reading the wind is the most important thing.

 

[Taildrag15X]

I gave the Sierra 90gr HPBT a try when they came out for Service Rifle, then when F-Class started I had a look again this time for my Prone Rifle and the thing I used for F/TR.

I never had bullets flying apart but much speed above 2,800 fps (1-7" Krieger, 30") saw accuracy fell off and the groups at 600 looked like buck shot.

The best part about them is you don't have to throat the crap out of the chamber to get enough powder behind them.....

 

[chkunz]

I gave the Sierra 90gr HPBT a try when they came out for Service Rifle, then when F-Class started I had a look again this time for my Prone Rifle and the thing I used for F/TR.

I never had bullets flying apart but much speed above 2,800 fps (1-7" Krieger, 30") saw accuracy fell off and the groups at 600 looked like buck shot.

The best part about them is you don't have to throat the crap out of the chamber to get enough powder behind them.....

The Sierra accuracy load states a velocity of 2600. Could it be that trying to get 2800 velocity is just asking too much? The wind drift for 2600 looks favorable compared to the 308. I have not shot any yet and you have so that is an important consideration. All I have to go on is the ballistics information and the experience of others. Thanks for sharing you experience..

 

[chkunz]

I calculated the recommended load for the 223 with the 90 grain bullet with the Powley Computer. I find it interesting that I got an answer so close to the Sierra accuracy load. The Powley load from the old 1961 cardboard slide rule was 24 grains of 4064 and an estimated muzzle velocity of 2670. I estimated the case capacity with the bullet seated which is one of the input parameters since I did not have an actual bullet to use for the measurement. Also I estimated the expansion ratio dimensions which involve case dimensions with the seated bullet and bullet length. My estimates are probably close but may have introduced some small error. Anyway the Powley computer answer is very close to the Sierra accuracy load of 22.4 grains of IMR 4064 and muzzle velocity of 2600.

 

[bigedp51]

I sent a email to Sierra asking if the they have updated pages, the 5th Edition came out in 2003 and is missing many new bullets and cartridges.

Below is the email reply.

Unfortunately, we no longer offer updated pages (that was discontinued some time ago) but I have a standing offer that if you have something that isn't listed in the manual, give me a call. Our 800 number is open and I'll do everything I can to help you find the information you're looking for.

Philip Mahin
Ballistic Technician
NRA Life Member
1400 W. Henry St. Sedalia, MO 65301
Questions? Call us toll free 800-223-8799

Check out my latest blog post at sierrabullets.wordpress.com.


-----Original Message-----
From: Sierra [mailto:sierra@sierrabullets.com]
Sent: Friday, August 07, 2015 8:31 AM
To: Philip Mahin
Subject: Reloading manual updates

Sierra Bullets

Is it possible to get the updated pages for the Sierra reloading manual 5th edition, third printing for your newer bullets and cartridges.

Thank You

 

[manitou210]

They were nice enough to sent me a copy of the complete page from the current manual that lists the 90 SMK. The accuracy load is 22.4 grains of IMR 4064 and a MV of 2600 fps. If I were sharp enough with the PC I would request permission to copy and paste the complete page here but that is beyond my skills. Just out of curiosity since the accuracy load turns out to be an IMR powder I am going to check it out on the Powley Computer and if I can get something that looks reasonable I will post that here. I am trying to figure out if it is feasible for the 223 with the 90 grain SMK to be competitive with the 308 for F T/R.

With BC of 500 ish they will be okay against 155 gr in .308 but you would be much better with Bergers 90 gr at 551 BC.
They will have same wind drift as the 185 gr Juggernauts