For many years, 8 decades really, the 270 Winchester has dominated the list of cartridges between 22 and 30 caliber. Until the 308 Winchester came along and spawned the 243 Winchester, other cartridges were overshadowed by the sheer perfection that is the 270 Win. The 25 and 26 caliber offerings just haven't done that well, as a result. If you wanted more than a hot 22 for varmints, you stepped up .050" to a 270, bypassing the options in-between, even though there have been many that were quite useful. The 270 Win was so good that, despite being in the top 3 listing of guns sold annually, the ONLY other commercially available cartridge of note, shooting .277" bullets, was the 270 Weatherby. In fact, Roy was offering the highest praise by imitating, with one of his very first rifles, the all-time classic Western deer cartridge.
This sounds like a love fest for the 270 Winchester, and I freely admit to being an unabashed fan, but my point is to illustrate why there are so few options available in 25 caliber. Aside from quite a number of interesting wildcats, there are only about five cartridges for the quarter-bore that have drawn more than a small amount of interest. In order of top velocity, they are the 250/3000 Savage, 257 Roberts, 25WSSM, 25-'06 and 257 Weatherby. Of these, the first two were once quite popular, the WSSM was a complete flop, and the 25-'06 has hung around, for good reason. The 257 Roy suffers the same fate as all Weatherby rounds; they are more expensive to buy and reload for, though they do provide a real step up, in performance.
If you are bound and determined to get a 25, the '06 or Bob is your best bet. Of the two, I frankly prefer the 257 Roberts. They are efficient cases with an appropriate amount of powder for the bullets and bore diameter in question, which gives handloaders an excellent round to load small bullets for varmints and heavier ones for medium-sized, thin-skinned game, like deer and wild hogs. The 25-'06 does the same, but IMHO, uses more powder than is really necessary for the job at hand. If you neck a 25-'06 up by .020", then ya got somethin'!
As a footnote: It has always perplexed me how the 308 Winchester could be such a great short-action cartridge, spawning a tremendously popular offspring in the 243, perhaps the best iteration of the case design, in the 7mm/08 and yet, wildcats in the 25/08 or 27/08 have simply not gained any popularity. Even the 260 Remington hasn't gotten much love, despite being a great little round. Some things just don't make sense, I guess.
