7.5X53.5 Swiss GP-90 for the M1889 rifle...

[Guncrank]

So anyone out there loading 7.5X53.5mm for the 1889 Schmidt Rubin rifle?

I recently received the fed.gov rebate on my hopelessly dismal lifetime investment in federal governance! This was, to my way of thinking wisely spent on a 90+% 1889 straight pull Swiss rifle. Obviously, a much superior investment than have been the dollars confiscated and squandered by our (fairly elected???) leaders.

Well? What have you successfully managed to assemble for your comely Swiss Miss and her shoosting needs???

GC

[ukrifleman]

Hi GC,

Here are some things that I have learnt along the way when loading for my 1889 Schmidt-Rubin.

First off, my 1889 will happily chamber 7.5x55 brass and I have found no need to trim cases back to 53.5, but try yours out first to make sure yours will do the same.

I always full length size cases, as the design of the bolt doesn't provide as much camming leverage as a Mauser type and it is much harder to chamber a round that needs the shoulders bumping back with the straight pull design.

I had problems using a K31 FL sizing die (Lee) as the shoulder angle on a K31 is not the same as earlier Schmidt Rubin's.

Hornady make 2 FL sizing dies for 7.5 Swiss straight pulls, one for the K31 and the other for older designs, I found their 7.5 Swiss die No.046361 just right for the 1889.

The original Swiss GP90 cartridge used a 213gn paper patched heeled lead bullet of .321 diameter, including the paper patch, the bare lead core measured .315.

The powder charge used was 29.0gn of SMOKELESS (not semi-smokeless) powder, giving a M/v of 1935fps and a service pressure of 37,000 psi. It is prudent at this stage to say do not fire modern GP11 ammunition from a Mod 1889.

I get good results using the Lyman 314299 200gn bullet, gas checked to .312.

I FL size my brass, then expand the case neck to .311 with a 31 long Lyman M die.

My powder of choice is Reloader 7, although there are others that perform well with cast bullets such as 5744.
I have never felt the need to shoot jacketed bullets through my 1889, but I am sure others will be along that do.

The 1889 has a 3 groove bore which is difficult to measure accurately and If you plan to slug it this is how I do it.

I have found easiest way to measure a slug, is to take a piece of copy paper, measure its thickness then wrap it tightly around the bullet, take a measurement then subtract twice the paper thickness.

Make sure that you wear eye protection, as the 1889 has a habit of allowing gas to blow back if you don't have a load that that provides a good chamber seal.

One final thing, Swiss army doctrine specified grease not oil to lube and maintain the rifle.

I hope this has been of help to you, the 1889 is a fine rifle to own and shoot.

Regards,
ukrifleman

[Guncrank]

ukrifleman,

Appreciate the info, especially as regards the Hornady sizing die! My Redding die set has worked very well for the K-31 but was totally unsuitable for the 1889. I was given a Lee die set and while it did size the case body correctly, it didn't push the shoulder back quite far enough. I ended up grinding 0.01" (0.254mm) off the top of a shell holder, screwing the die down just a bit more and the brass now glides in smooth as silk.

As to powders, given the current state of no-availability, I'm trying what I had on hand. TrailBoss did work but velocity was way down in the 1400 fps area pushing a 180g bullet. Others such as AA2520, AA2230 and a couple of "canister" powders were either downright filthy or left significant amounts of unburned powder behind. Best charge for the 180g bullet I'm using has been IMR4895 which not only is burning cleanly but pushing the the bitter pill out the muzzle at 1750 fps. It's also filling the case nearly 2/3's full.

My opinion:
As 4895 was the powder of choice when the 30-06 was adopted it should be in the near neighborhood as regards burn range to the original Swiss powder given that the case capacities are somewhat similar.

As of this writing I've not had the opportunity to do more than 35 yard accuracy and velocity testing, but the Swiss Miss sure is looking to be 2 to 3 MOA capable! As long as I do my part.

GC

[Guncrank]

The weather here today afforded me the opportunity to try my hand loads at 300 yards on a 3/4 (12"x20") size IPSC steel plate. The results with a 10 to 20 MPH gusty cross wind were VERY satisfying! 12 of the 18 shots fired rang the steel plate! Given the sorry state of my eyesight, well, I just couldn't be more pleased with my Swiss Miss!

As a point of interest I checked capacity of a Lake City 30-06 case as compared to the NNY 7.5x55 brass I'm using by filling them with IMR-4895. I was rather shocked to find that the LC 30-06 case held only 3/4 of a grain more powder than the NNY case! I had really suspected the difference would be something on the order of 5 grains.

Now it's just going to be a matter of fine tuning the load(s).

[Eddie1971]

I use the 314299 and the NOE 312299 with 36 grains of IMR4350. Shoots great and real mild.