Brybenn,
Just to straighten things, the 146 was only chambered in 9.3x57. Apart the 1640, only the 640/1000/1100 were chambered in '06 and the 1640 were never made in 9.3x57.
Now regarding the actions themselves, the 1640 is a compound of both m/98 and m/96.
It uses the m/98 action lenght, #### on open and the three lugs bolt.
It also uses the m/96 front bolt lugs and breeching system.
Then, unlike the two Mauser designs, it has a non splitted left side front lug and a modified escaping gas feature of it's own.
It's only forged with modern steel.
Finally, the FN actions used by HVA have the military style bolt shroud while the 1640 uses a more scope friendly strealined bolt with side safety.
The 1640 is a very strong action and was chosen to handle the 358 Norma Magnum.
At the end, the main difference between the FN 98 and the 1640 is that the 1640 is a small ring action while the FN 98 is a large ring action.
One thing of interest is that FN ntroduced their Supreme action only in 1956 and that it's shaped like the 1640 (introduced 1953)
As for comparing a P-H 98 to both rifles, the early P-H use a standard m/98 action with shroud mounted flag safety while the later use a "commercial" action which is a copy the FN Supreme.
For a picture of the above, see in the HVA rifles sticky, post # 9, I posted a picture of the HVA 1640, FN Supreme and HVA 640 bolts to compare.
http://www.canadiangunnutz.com/forum/showthread.php/486796-Husqvarna-Sporting-Rifles-####-ALL-MODELS!!!
