OSP conversion

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J-team1

OSP conversion

Post by J-team1 »

I appologise if this has already been covered on another thread, but is there any info on or pics of the conversion of a Walther OSP to be a Standard/Sport pistol.

I remember in the early 1990s seeing a woman shooter on the US National Team using one in a World Cup for Sport Pistol. It was built on an OSP frame and it had small weights on the bolt lugs that looked like the ones on a GSP .32 only smaller.

Any help would be appreciated.
MichaelB
Posts: 23
Joined: Sun Jul 15, 2007 7:07 pm
Location: Western Australia

Post by MichaelB »

The manuals I've seen on-line for the Walther OSP/GSP suggests that they are simply converted by changing the barrel and the trigger unit: they were designed that way.

In fact, I've been told that "all (Walther GSP and OSP) parts for the last thirty years" are effectively interchangeable, including the early and later trigger units.

This seemed too good to be true, so I wonder if it is.
Spencer
Posts: 1889
Joined: Fri Feb 24, 2006 9:13 pm
Location: Sydney, Australia
Contact:

Re: This seemed too good to be true, so I wonder if it is.

Post by Spencer »

Given the way Barry C and I have changed barrel/slide combinations (including .22 shot converted to .22LR) while trying out ammunition, etc.

Yes

Spencer
MichaelB
Posts: 23
Joined: Sun Jul 15, 2007 7:07 pm
Location: Western Australia

Post by MichaelB »

"Yes", too good to be true? I'd appreciate more detail if you can.
Fred

Post by Fred »

Do a search on TT for OSP conversion and Sandy Santibanez. Sandy built the OSP conversion that his daughter, Lauren, used on the USST. He posted detailed instructions for the conversion on TT. Do NOT simply substitute a LR barrel for the Short barrel. You will end up with a badly battered frame in a very short time.

HTH,
FredB
J-Team1

Post by J-Team1 »

MichaelB wrote:The manuals I've seen on-line for the Walther OSP/GSP suggests that they are simply converted by changing the barrel and the trigger unit: they were designed that way.
Perhaps there is a mis-understanding here. I'm not talking about conversion kits which are the complete upper barrel and slide, but using an OSP upper to convert (a they are now useless) it .22lr.

Fred is correct in that the OSP slide is much too light for a .22lr and would cycle way too fast and just wreck the pistol. The added weight slows it down and (hopefully) prevents damage!

I would like a pic if anyone has one.
shadow
Posts: 358
Joined: Tue Nov 15, 2005 7:56 pm

From OSP To GSP

Post by shadow »

I aslow want to do the same thing. Here is the info from this website:





Joined: 01 Jul 2004
Posts: 165

Posted: Wed May 25, 2005 4:32 am Post subject: Walther OSP reborn

--------------------------------------------------------------------------------

Hi,
The old OSP can be alive as a .22LR

1. New liner in the barrel.
2. Reshape grip to comply with rules.
3. Replace handles with those from a .32 to add weight.
4. Move front sight back to comply with rules. (Drill and thread)
5. New mag. (From an other GSP .22LR perhaps)
6. New trigger (From an other GSP .22LR perhaps)

With Lapua Pistol King it makes 255 m/s and works fine.

Kent

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Pär Hylander



Joined: 28 Dec 2004
Posts: 34
Location: Sweden
Posted: Wed May 25, 2005 4:57 am Post subject:

--------------------------------------------------------------------------------

Yepps!

3. Probably only if newer style light slide/bolt (which is the correct name of it?).
6. Perhaps only a harder spring behind the trigger will do it

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Sandy



Joined: 03 Mar 2004
Posts: 97
Location: San Diego, CA
Posted: Thu May 26, 2005 10:09 am Post subject: OSP/GSP CONVERSION (long post)

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You do not have to do everything that I did. Check that .22LR magazines fit your pistol (some do not).

All you need is;
1. A stock .22LR barrel, .22LR magazines and a 1000g trigger from Walther.
2. The .32 caliber cocking handles (make them smaller so that they are not so heavy, or machine them like hers).
3. The plastic tubing (to act as a buffer). This is necessary.
4. Move the front sight back to be ISSF legal.
5. Modify the grip to be ISSF legal.

You will probably have to tune the weight of the cocking handles and the length of the buffer for the ammunition that you use. Easy to do. My modification works very well with all the match ammunition that we used but you should plan on fine tuning everything to your ammunition.

The Bo-Mar sight modification was done because for the Precision stage she used a sub six hold with a narrow blade opening and for the Duel stage she used a center hold with a wide blade opening. These are features that are not really necessary but were helpful for her particular needs.

The following are the photos and captions for the OSP/GSP Conversion
.
Print and line them up in groups as labeled.

A-1 The right side, showing World Cup & World Championship equipment control stickers.

A-2 The left side, note that Lauren has small hands, even for a 5’5” girl. She is a lefty.

A-3 Top view with grips removed (note the barrel, sights and charging handles).

B-1 Right side, note the chamfering and the lightening slots on front of frame.
Note the rear sight position.

B-2 Left side is the same. The serial number had to be relocated because of the
lightening slot
.
B-3 The Top of Slide Casing showing the chamfering and the lightening slot on the top.

C-1 Top barrel is Custom made by Falcon Machining Ltd. In Scottsdale, Arizona.
The sides have been milled to get the correct balance.
Bottom barrel is a Walther, with chamfers and the front turned down on a lathe.
It has lead wheel weights for more weight when she was older and stronger.

C-2 Top Barrel is the Walther with the wheel weights removed.
Bottom barrel is the Falcon.

C-3 The top one, the Falcon barrel, shows how the front sight is dovetailed on its length.
The bottom one, the Walther barrel shows how the front sight is dovetailed across.

D-1 The custom cocking handles on the .32 cal cocking handle bolt that goes through the breechblock. The recoil buffer is slotted to fit around the spring. It is a section of plastic tubing 3/8” I.D. X 9/16” O.D. (aprox. ¾ inch (19mm) long). It has thousands of rounds of use.

D-2 The other side of the cocking handles and an end view of the recoil buffer.

E-1 Top cocking handle is the custom one for the conversion,
(With the Allen bolts the pair weigh 51 grams).

The bottom one is a stock .32 cal from Walther,
(With the Allen bolts the pair weigh 73 grams).

On the left is a custom dovetailed front sight (not used on this pistol but shown so that you can see what it looks like milled for the Falcon barrel).
On the right is a new recoil buffer showing the slot to fit on the recoil spring.

E-2 Same as E-1 showing different views of the cocking handles, front sight and recoil buffer. Note the large Allen bolt holes on the Walther. The walls would be very thin and weak if milled to lighten them, therefore the custom cocking handles with smaller Allen bolts is better.

F-1 The custom Bo-Mar rear sight installation, slight top view.

F-2 Same as F-1, slight bottom view.
Note the detent in the sight to zero the sights when the changing sights..
Note the screw of the micro plunger in the frame for the detents.

Some pistol smiths may find this feature is challenging to machine and install. A small hex bolt on each side of the sight locks the sights down.

The sight modification works extremely well and the sights are always perfectly positioned after the change because of the small spring-loaded plunger in the frame and a detent centered in the bottom of each sight.

One sight is zeroed for sub 6 hold for the Precision Stage with a narrow slot.

The other sight is zeroed for the Duel Stage using a center hold. It has a wider slot making it easier to see the front sight against the black of the target.

Changing the sights takes less than 20 seconds to make. It is done on the line between stages while the other shooters are trying to adjust their sights by counting clicks.

The photos are self-explanatory instructions. Have a competent pistol smith that is familiar with Walthers do the conversion.

www.targettalk.org/images/Attachments/OSPConv/A-1.jpg
www.targettalk.org/images/Attachments/OSPConv/A-2.jpg
www.targettalk.org/images/Attachments/OSPConv/A-3.jpg
www.targettalk.org/images/Attachments/OSPConv/B-1.jpg
www.targettalk.org/images/Attachments/OSPConv/B-2.jpg
www.targettalk.org/images/Attachments/OSPConv/B-3.jpg
www.targettalk.org/images/Attachments/OSPConv/C-1.jpg
www.targettalk.org/images/Attachments/OSPConv/C-2.jpg
www.targettalk.org/images/Attachments/OSPConv/C-3.jpg
www.targettalk.org/images/Attachments/OSPConv/D-1.jpg
www.targettalk.org/images/Attachments/OSPConv/D-2.jpg
www.targettalk.org/images/Attachments/OSPConv/E-1.jpg
www.targettalk.org/images/Attachments/OSPConv/E-2.jpg
www.targettalk.org/images/Attachments/OSPConv/F-1.jpg
www.targettalk.org/images/Attachments/OSPConv/F-2.jpg

Sandy Santibanez
J-Team1

Post by J-Team1 »

Shadow,

Thank you so much. That's exactly the info I was looking for.
fat-tony
Posts: 26
Joined: Tue Sep 11, 2007 5:12 pm
Location: Ireland

Re: OSP conversion

Post by fat-tony »

J-team1 wrote:I appologise if this has already been covered on another thread, but is there any info on or pics of the conversion of a Walther OSP to be a Standard/Sport pistol.
I note that you are logged on a guest - whereabouts are you based? You can pick up 2ndhand GSPs in Europe at a fraction of the probable cost of converting an OSP barrel, trigger, grip, sights etc....
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