Smith & Wesson Forum

Go Back   Smith & Wesson Forum > Ammunition-Gunsmithing > Ammo
o

Notices

Ammo All Ammo Discussions Go Here


Reply
 
Thread Tools Display Modes
  #1  
Old 08-04-2017, 02:11 PM
bigwheelzip's Avatar
bigwheelzip bigwheelzip is offline
Absent Comrade
Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun?  
Join Date: Dec 2014
Location: Upstate SC
Posts: 12,990
Likes: 17,229
Liked 41,503 Times in 9,146 Posts
Default Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun?

For a few years, fairly regularly, I'd read that some owners of .44mag rifles are unhappy with their accuracy. Yesterday, I saw a post where an owner slugged his rifle barrel and saw a difference in bore dia. compared to his handguns.

The answer came back that both guns are correct and that SAAMI has different specs for each. I just checked, and found these bore specs, Handgun .417, Long gun .424.

Seems that some factory rounds are somewhat loose fitting in some long gun barrels, requiring larger handloads.

I checked two other common pistol calibers also used for rifles, .357Mag and .45 Colt, and there is no separate rifle spec like there is for the .44mag.

Does anyone here know why these bores need to be different?

Last edited by bigwheelzip; 08-04-2017 at 04:58 PM.
Reply With Quote
  #2  
Old 08-04-2017, 02:40 PM
Pisgah Pisgah is offline
Member
Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun?  
Join Date: Nov 2005
Location: Upstate SC
Posts: 3,439
Likes: 37
Liked 5,413 Times in 1,756 Posts
Default

Try as I may, I cannot find any reference to SAAMI bore diameter specs. Perhaps someone can give me a reference. Cartridge and chamber specs, yes; bore specs, no. The only reference I can find is a listing of nominal bore diameters for various cartridges, and that says .44 Magnum is .430, with no distinction between the rifle and handgun. The reason for slugging a bore in the first place is that various manufacturers use different bore specs for all sorts of cartridges.
__________________
Pisgah
Reply With Quote
The Following 2 Users Like Post:
  #3  
Old 08-04-2017, 02:43 PM
bigwheelzip's Avatar
bigwheelzip bigwheelzip is offline
Absent Comrade
Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun?  
Join Date: Dec 2014
Location: Upstate SC
Posts: 12,990
Likes: 17,229
Liked 41,503 Times in 9,146 Posts
Default

These are from SAAMI | Sporting Arms and Ammunition Manufacturers' Institute Handgun on Page 166, Rifle on Page 339

The bore and groove dim is at the upper right of both drawings.




Last edited by bigwheelzip; 08-04-2017 at 02:57 PM.
Reply With Quote
  #4  
Old 08-04-2017, 04:46 PM
robertrwalsh robertrwalsh is offline
SWCA Member
Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun?  
Join Date: May 2008
Location: Peoples Republic of Calif
Posts: 4,644
Likes: 1,226
Liked 5,988 Times in 2,133 Posts
Default

I have to admit that surprises me.
Reply With Quote
The Following 2 Users Like Post:
  #5  
Old 08-04-2017, 05:32 PM
WR Moore WR Moore is offline
Member
 
Join Date: Oct 2006
Posts: 6,580
Likes: 1,787
Liked 5,342 Times in 2,685 Posts
Default

OK, there's a clue is in the title of the drawings: VPI TEST BARREL. You'll note the inclusion of location of the pressure sensor. You'll also note on the rifling specs that the rifle has 12 grooves, the pistol 6 grooves. It would appear that the rifle test barrel is for Marlin micro-groove rifling, the pistol for conventional rifling.

With a specified groove diameter, bore diameter is going to vary depending upon depth of the rifling. Conventional rifling is deeper, so the bore diameter will be less.

That said, recall that test barrels are designed to create worst case scenarios FOR THE AMMO MANUFACTURERS from the variations that manufacturers are will create. Given various different rifling profiles, there may well be different pressure test barrels to suit the various/dominant rifling profiles for any given caliber.

Last edited by WR Moore; 08-04-2017 at 05:36 PM.
Reply With Quote
The Following 2 Users Like Post:
  #6  
Old 08-04-2017, 06:15 PM
MichiganScott MichiganScott is offline
Member
Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun?  
Join Date: Jan 2012
Location: God's Country
Posts: 4,711
Likes: 1,235
Liked 3,535 Times in 1,770 Posts
Default

Take note of the twist rate of the rifle. That is the biggest reason some .44 Mag rifles have accuracy issues. I would imagine it is compounded by loose bullet fit.

I have an early issue Ruger Deerstalker.The iron sighted groups aren't much smaller than my M29 using 240gr. ammo.
Reply With Quote
The Following 2 Users Like Post:
  #7  
Old 08-04-2017, 06:24 PM
armprairie armprairie is offline
Member
Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun?  
Join Date: Jan 2014
Location: Central Illinois
Posts: 23
Likes: 13
Liked 37 Times in 16 Posts
Default Use Internet Explorer for Saami

Saami Specs are set up to be viewed only with Internet Explorer. So I start out on Microsoft Edge, then hit the three dots on the upper right that pulls down a menu so you can switch to Internet Explorer.
What your really want is the cartridge and chamber drawing in the "Rifle" section which will be marked page 143. Just put the little hand on 44 Remington Magnum and click it, then you can view it or print it by printing the current page. Note that this is actually page 155 of the specs, there are several pages of introductory stuff.
Marlin must have been the first to submit the Saami spec and they were calling for the 12 groove shallow Micro-grooves with the 1 in 38 twist, hence the .424 bore,.431 groove with a plus .004" tolerance (that's right, you could have a .428 bore and .435 groove and just be at the edge of the tolerance). Marlin may have changed that later in their own internal processes, I'll check with Glen Fryxell. The Saami specs are voluntary of course. A manufacturer using conventional rifling would have a smaller bore.
Reply With Quote
The Following User Likes This Post:
  #8  
Old 08-04-2017, 06:42 PM
DWalt's Avatar
DWalt DWalt is online now
Member
Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun?  
Join Date: Dec 2009
Location: South Texas & San Antonio
Posts: 33,481
Likes: 236
Liked 28,944 Times in 14,013 Posts
Default

"Saami Specs are set up to be viewed only with Internet Explorer. "

Not aware of that. Firefox and Opera work fine for me.
Reply With Quote
  #9  
Old 08-04-2017, 07:40 PM
bigwheelzip's Avatar
bigwheelzip bigwheelzip is offline
Absent Comrade
Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun?  
Join Date: Dec 2014
Location: Upstate SC
Posts: 12,990
Likes: 17,229
Liked 41,503 Times in 9,146 Posts
Default

Quote:
Originally Posted by armprairie View Post
Saami Specs are set up to be viewed only with Internet Explorer. So I start out on Microsoft Edge, then hit the three dots on the upper right that pulls down a menu so you can switch to Internet Explorer.
What your really want is the cartridge and chamber drawing in the "Rifle" section which will be marked page 143. Just put the little hand on 44 Remington Magnum and click it, then you can view it or print it by printing the current page. Note that this is actually page 155 of the specs, there are several pages of introductory stuff.
Marlin must have been the first to submit the Saami spec and they were calling for the 12 groove shallow Micro-grooves with the 1 in 38 twist, hence the .424 bore,.431 groove with a plus .004" tolerance (that's right, you could have a .428 bore and .435 groove and just be at the edge of the tolerance). Marlin may have changed that later in their own internal processes, I'll check with Glen Fryxell. The Saami specs are voluntary of course. A manufacturer using conventional rifling would have a smaller bore.
I found the page you were talking about.

Reply With Quote
  #10  
Old 08-04-2017, 08:05 PM
WR Moore WR Moore is offline
Member
 
Join Date: Oct 2006
Posts: 6,580
Likes: 1,787
Liked 5,342 Times in 2,685 Posts
Default

Since whenever that rifle spec above was submitted, I believe that Marlin went to "Ballard type" rifling in the .44 Magnum.
Reply With Quote
  #11  
Old 08-04-2017, 08:13 PM
bigwheelzip's Avatar
bigwheelzip bigwheelzip is offline
Absent Comrade
Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun?  
Join Date: Dec 2014
Location: Upstate SC
Posts: 12,990
Likes: 17,229
Liked 41,503 Times in 9,146 Posts
Default

So if I understand you guys right, the same SAAMI bullets traveling down the two different bores diameters should react properly because of the different rifling designs.

So when these owners load a larger diameter bullet and get better accuracy in the rifle, it's not because of the larger bore, it's because of the design and twist of the rifling, and maybe some dimensional variation.

No wonder I see people questioning their rifle's accuracy. Seems unnecessarily complicated.

Thanks guys for making the effort to explain this art y'all are so good at.
Reply With Quote
  #12  
Old 08-04-2017, 08:18 PM
bigwheelzip's Avatar
bigwheelzip bigwheelzip is offline
Absent Comrade
Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun?  
Join Date: Dec 2014
Location: Upstate SC
Posts: 12,990
Likes: 17,229
Liked 41,503 Times in 9,146 Posts
Default

Quote:
Originally Posted by WR Moore View Post
Since whenever that rifle spec above was submitted, I believe that Marlin went to "Ballard type" rifling in the .44 Magnum.
It says this on their site:

20” barrel with deep-cut Ballard-type rifling (6 grooves)

1:38” twist rate
Reply With Quote
  #13  
Old 08-04-2017, 08:30 PM
bigwheelzip's Avatar
bigwheelzip bigwheelzip is offline
Absent Comrade
Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun?  
Join Date: Dec 2014
Location: Upstate SC
Posts: 12,990
Likes: 17,229
Liked 41,503 Times in 9,146 Posts
Default

Using some of what I just learned here I came across an article that covers this.

"Also in the 1960s, Marlin introduced the .44 Magnum to the Model 336. This rifle was fitted with Microgroove barrels, containing 12 grooves that were .062" wide and .0043" deep. Factory specs for the .44 Magnum barrels also called for a 1 in 38" twist, but that this time nominal groove diameter was to be held to .4315", and a bore diameter of .4230", so oversized cast bullets are once again called for."

Later in the article it says:

"As of fall of 2007, Marlin still makes a number of guns that have Microgroove barrels on them (according to the 2007 Marlin catalog posted on their website). All of their .22 LR and .22 Magnum rifles still have Microgroove barrels. The 336s in .30-30 and .35 Remington are still made with Microgroove barrels, however the stainless 336XLR in .30-30 and .35 Remington have Ballard rifled barrels. All of the big-bore Marlin leverguns (e.g. 444, 1895, etc.) are now fitted with Ballard rifled barrels (both blued and stainless guns), as are the 1894 and 1895 Cowboy models. Interestingly, in the 1894 series, the.44 Magnum and .357 Magnum guns are Ballard rifled, but the .32-20 1894CL and .41 Magnum 1894 FG are both fitted with Microgroove barrels."

So it seems they eliminated the Microgroove in 2007 for the .44 magnum caliber in question.

Thanks again guys, I wouldn't have found it without you.

I wonder if this need to use oversized cast bullets is mentioned in the owners manual, and how many frustrated factory ammo shooters this created.

Last edited by bigwheelzip; 08-04-2017 at 08:41 PM.
Reply With Quote
  #14  
Old 08-04-2017, 09:06 PM
armprairie armprairie is offline
Member
Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun?  
Join Date: Jan 2014
Location: Central Illinois
Posts: 23
Likes: 13
Liked 37 Times in 16 Posts
Default It does cause a lot of frustration!

It certainly does cause a lot of frustration, not only in the .44, but in the .357 and .41. A friend of mine has one in .357 that will shoot jacketed just fine, but no good with lead unless he wants to keep one batch of bullets sized so large they won't even fit into the throats of his revolvers. His Winchester 94 handles both just fine. The newer Ballard rifling would probably work just fine with both. The bullet size does make a huge difference with the Marlin Micro-groove, as it does with the 30-30 from my experience, but moreso with the pistol calibers.
This is a real common discussion over on the cast bullet websites. Glad someone went to the trouble of quoting Glen Fryxell's comments on this.
Reply With Quote
  #15  
Old 08-04-2017, 09:26 PM
bigwheelzip's Avatar
bigwheelzip bigwheelzip is offline
Absent Comrade
Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun?  
Join Date: Dec 2014
Location: Upstate SC
Posts: 12,990
Likes: 17,229
Liked 41,503 Times in 9,146 Posts
Default

Quote:
Originally Posted by armprairie View Post
It certainly does cause a lot of frustration, not only in the .44, but in the .357 and .41. A friend of mine has one in .357 that will shoot jacketed just fine, but no good with lead unless he wants to keep one batch of bullets sized so large they won't even fit into the throats of his revolvers. His Winchester 94 handles both just fine. The newer Ballard rifling would probably work just fine with both. The bullet size does make a huge difference with the Marlin Micro-groove, as it does with the 30-30 from my experience, but moreso with the pistol calibers.
This is a real common discussion over on the cast bullet websites. Glad someone went to the trouble of quoting Glen Fryxell's comments on this.
Don't recall seeing those other calibers causing people problems, only .44. Might be that more .357 shooters use jacketed. I'll keep it in mind though.
Reply With Quote
  #16  
Old 08-07-2017, 09:36 AM
DWalt's Avatar
DWalt DWalt is online now
Member
Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun?  
Join Date: Dec 2009
Location: South Texas & San Antonio
Posts: 33,481
Likes: 236
Liked 28,944 Times in 14,013 Posts
Default

The early Marlin Model 1895 (the modern 1895) rifles in .45-70 had microgroove rifling. That was fine as long as jacketed bullets were used. But it was soon discovered that microgroove didn't work so well for lead bullets. I don't know how long it took, but Marlin did go back to Ballard rifling for the 1895. I once had an early 1895 and I can attest to that problem. It grouped well when I used jacketed bullets, but like a shotgun with lead bullets. I did come up with lead bullet loads which didn't group too badly, but still not so good. Surprisingly, that 1895 grouped better with lead bullets and black powder rather than with smokeless powder. I did a lot of load experimentation with that 1895 back in the early 1980s and kept records, but I have no idea where those records are today. Probably long gone.
Reply With Quote
The Following 2 Users Like Post:
  #17  
Old 05-16-2020, 04:01 PM
WPWarhawk's Avatar
WPWarhawk WPWarhawk is offline
Member
Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun?  
Join Date: Jun 2004
Location: Hot Springs, Arkansas
Posts: 649
Likes: 293
Liked 570 Times in 198 Posts
Default

Quote:
Originally Posted by bigwheelzip View Post
Don't recall seeing those other calibers causing people problems, only .44. Might be that more .357 shooters use jacketed. I'll keep it in mind though.
It has a lot to do with twist rates. 357 and 45 Colt rifles have the same twist as the handguns, usually 1:20. The 44 handgun is 1:20 while the rifle is 1:38.

I can cast bullets oversize to compensate for the oversize bore, but there is nothing I can do about the twist rate, short of rebarreling.
Reply With Quote
  #18  
Old 05-18-2020, 04:17 PM
Skeet 028 Skeet 028 is online now
Member
Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun? Why Does SAAMI Spec Have Different .44Mag Bore Dia For Rifle And Handgun?  
Join Date: Feb 2010
Location: Wyoming
Posts: 6,137
Likes: 6,330
Liked 7,047 Times in 2,984 Posts
Default

I gave my father in law a 1894 in 44 mag. Shot jacketed bullets fine. forget lead..was terrible. I also had a 1895 45-70 like DWalt had. Jacketed was fine. A friend??(I questioned that at the time) gave me 90 pounds of cast sized lubed bullets. Only one of the 6 different bullets shot worth a darn. The rest were almost as bad as long range buckshot groups. I sold that sucker and got the newer Cowboy model with Ballard rifling and it wil shoot almost any lead bullet well....But it does have a safety.
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Favorite big bore handgun ? AveryR S&W Revolvers: 1980 to the Present 130 03-26-2017 12:49 PM
First Rifle-S&W M&P15 CA Spec LabRatLAA Smith & Wesson M&P15 Rifles 3 09-12-2016 06:59 PM
What's the best legit place online to buy handgun ammo (44mag and 357mag)? xssv Ammo 10 09-15-2014 07:46 PM
Big Bore Handgun Heavyweights Update flat top Reloading 64 03-02-2010 09:16 PM
Big Bore Handgun Heavyweights. flat top Reloading 14 12-06-2009 03:51 PM

Powered by vBadvanced CMPS v3.2.3
smith-wessonforum.com tested by Norton Internet Security smith-wessonforum.com tested by McAfee Internet Security

All times are GMT -4. The time now is 08:32 PM.


Smith-WessonForum.com is not affiliated with Smith & Wesson Holding Corporation (NASDAQ Global Select: SWHC)