Might not be the best sporting rifle project but…

My new found friend "Bokmal" asked me to post this... so blame him if this sucks...

It all started as a joke… My friend and I were playing around with the thought of making a “big game rifle” based on a Mosin Nagant. My friend is a Mosin collector and has a vast knowledge in this excellent piece of machinery. The idea was to create an ideal weapon for elk hunting in Finland. Both of us are hunting in areas thick with vegetation and quite short shooting distances. We decided on the .458 as the bullet diameter. We had considered both .45-70Gmnt and .450Marlin, but both would have required a lot of work on both bolt and action. The caliber, for our project, would become .45x54R and be based on the 7,62x53R. This meant that we wouldn´t have to do any changes on the bolt, only the magazine body.

This caliber, was no new invention, because there have been guns registered in Finland in calibers that are very similar to ours. For example 11,6x55R made by Erkki Maekinen and .458x53R Gunhill made by Jarmo Kauppinen. I´m sure, that other similar calibers exist. Maekinen used an old Arisaka model 30 as base and Kauppinen the “Russian” Winchester model 1895. As Maekinen´s 11,6x55R, also our .45x54R, was to be made using case-blanks from Sako. These Sako case-blanks where marked 12,4x55R and picked out of the production line before they would be necked down to 7,62x53R . Ours would be shortened to 54mm. Kauppinen used both Sako case-blanks and 9,3x53R caliber cases which he necked up to fit a .458 bullet. Reloading of brass, would be done using 45-70Gvmnt reloading dies.

The idea was to get the same effect out of our caliber as from the hottest .45-70Gvmnt loads. This is certainly possible because the parent case 7,62x53R tolerates higher pressure than the .45-70Gvmnt, even though the .45-70Gvmnt case has a volume advantage of 3%. Testing in this matter is still on-going, but the little testing we have done, suggests that .45x54R is a very potential caliber. So far I have been able to get 2200fps from a 300grain Hornady Interlock HP bullet, without any pressure indications what so ever. This is more than enough to kill anything one might encounter in the Finnish forest. One of the advantages, compared with the .45-70, is that we don´t have to seat the heavier bullets all the way to the crimp-groove, thus leaving more room for gunpowder.

(From left to right: 400gr Remington CoreLokt modified to RN, Hornady 300gr HP modified to Semi-SPTZ, an expanded 9,3x53R case with a H&N 300gr)

Enough about the caliber... more about the gun…

My friend bought a box of Finnish Mosin Nagant parts from a gunfair in Tampere. That box included the bolt, reciever and magazine body and it only cost 60euros. My friend already had a complete reciever with parts for himself. He also found a second hand .458 barrel from a 45-90 black powder rifle for himself. I found my barrel on-line on a website for hunters in Finland. It was a new barrel made by Erkki Maekinen. Both barrels have the same 16´ twist, but my friend has a longer (barrel!!)…

I modified my magazine body simply by cutting it open and straightening out the grooves for the shoulder and expanding it in the front end. Then all was welded together by a professional welder. The magazine body now fits 4 bullets and one can empty it the normal way, by opening the floorplate. The magazine body was sandblasted, to get rid of old tool marks and scratches and finally blued.

The barrel and other parts were sent to a gunsmith, Alpo Tapper, in Lannevesi near Jyvaeskylae in Finland. Alpo also made the reamer for the .45x54R. The headspace gauges are the same for the 7,62x53R, so he didn´t have to worry about them. He modified the bolt handle to look like it was from a TAK-85 and also made a ring safety cocking knob. The side-mount with a weaver rail he machined from a piece of metal. This is his design and is firmly attached with two hefty screws. This design makes the otherwise “soft” Mosin receiver a little bit steadier, improving accuracy, not that it much matters in a caliber like this.

After a mandatory test-shooting in Riihimaeki (at the old Sako factory where the police test-shooting lab is), I finally got all the pieces home and could start putting everything together. By that time I had also received the stock I had ordered from Boyd´s Gunstocks. It took me quite a lot of elbow grease and a lot of sandpaper, to get the barrel to fit the stock that was made to fit an original Mosin in caliber 7,62x53R. I finally got it fitted though. A mounted a Tikka Pro Gold 1,75-6x22 on it with a pair of Quick-Site weaver rings and was itching for a test shoot…

After the test shoot I ended up fixing the stock and fitting a proper recoil plate in the stock. That because the stock split in half just after 10 shots. This is fixed now and I´ve also made proper bedding with Acraglass Gel. The stock splitting could have been avoided, but when you have an itch… you just have to scratch…

This one might kick like a mule, but is still very nice to shoot. Much softer recoil, i might add, than the 9,3x53R Finnish!!!