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Old 07-06-2009, 09:43 AM
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Hoptob Hoptob is offline
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Post Duplicating Buffalo Bore FBI Load

For awhile now I’ve been impressed with Buffalo Bore awesome 158 gr. lead SWCHP 38 special load (#20A). Clocked at over 1040 fps from 2” bbl and 1160 fps (!) from 4” bbl, BB FBI load is without a doubt the most powerful 38 special load on the market today. Who says 38/44 is a thing of the past?

As a reloader I always wanted to replicate it. What does it take to get this type of ballistics in 38 special? Can it be done within +P limits? Tim Sundles who developed this load used to post on THR. People often asked him these questions. Tim provided some information but it only added to the mystery around his load. Over time Tim stated that:
  1. BB #20A load is within SAAMI pressure limit
  2. It is safe to fire it in any modern 38 special +P revolver in a good operating condition
  3. He uses flash-suppressed non-canister powder which is not available in stores
  4. To protect BB trade secrets he will provide no further information
A few months back a member of this forum, 336A, posted that Rimrock Bullets Co. sells 160 gr. soft lead SWCHP bullets used in BB load – link. Thanks, 336A! I bought some of them and can confirm that it is in fact the same bullet.

With the right bullet in hand, my BB FBI load duplication project was off to a good start. First things first – I broke one of the BB rounds. Inside the case I found 7.5 gr. of a flake powder. It looked somewhat similar to SR4756 but it wasn’t same. Below are close-up shots of the two powders taken at 11x magnification. You will see that BB flakes are smaller and thicker than SR4756.



Looking at these pictures someone may wonder if they were taken with an expensive lab microscope. Nothing of the kind, folks. I used my trusty 8 y.o. consumer digital SLR equipped with 20 y.o. 50 mm Nikon lens ($85 at the time) and a set of extension rings worth $60 NIB. It’s honest backyard science, folks, no cheating

Now, BB load is charged with 7.5 gr. of powder. We can assume that it must be one of the medium burn rate powders, not the likes of Bullseye or 2400. After studying recent and not so recent manual, I chose four powders to work with – HS-6, Longshot, SR4756 and VihtaVuori N340. All handloads were built as close as possible to BB load, except for less crimp. I did apply firm crimp but stopped short of making crimp line simply to extend service life of my brass. I found that bullets were held very securely without excessive crimp. It took over dozen good hits with Dillon bullet puller to break these rounds; normally I consider 5-6 hits to be good enough.


Buffalo Bore FBI load (left) and handload (right); Rimrock 160 gr. SWCHP. All handloads were made with Rimrock bullets,
S&B 38spl cases; OAL 1.46”; firm crimp. Primers: Rem 1-1/2 in N340, Longshot and SR4756 loads; Win SPM in HS6 loads.


BB load clocked 1044 fps in my 2-1/4” bbl SP101 – exactly as advertised. After several extended load-building and chronographing sessions, I found out what powder charge is needed to get same velocity in my handloads. Here it is:



Here you have it - four replicas of Buffalo Bore FBI load.

For those who want cheaper training load – I suggest that you try TVB 158 gr. SWC instead of Rimrock SWCHP. Rimrock makes wonderful soft hollow point bullet. It's close to perfect for self defense snubby loads but it is also rather expensive as far as training goes. I see no reason to punch holes in the paper with a $18.50/100 lead slugs. TVB bullets sell for almost 3 times less; in my tests they clocked at almost same velocity as Rimrock's and produced no leading at BB velocities. TVB bullets are available from a member of this forum Jessie aka NKJ Nut - Tennessee Valley Bullets.

Naturally, all of my BB replicas were well above published load recommendations for 38spl+P. FWIW, pressure calculations placed HS-6 and Longshot loads in 26,000-27,000 range; N340 and SR4756 were running a bit higher. Primers showed moderate deformation consistent with this range of pressures.



Does any of this mean that BB load has to be above +P pressure limit? Not at all. It is entirely possible that Tim Sundles’ secret flake powder allows him to reach 38/44 ballistics with 38spl+P pressures. The only way to find out would be to have his load tested by H.P. White or another reputable lab.



I have to say that I am not too concerned with the load pressure. My steel frame Colt Detective Special is quite happy with Buffalo Bore FBI load. And so am I.

Mike
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Last edited by Hoptob; 12-26-2010 at 03:34 PM. Reason: fixed broken links
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