A friend is having a dispute with his daughter's teacher over how many shofar blasts are traditional for Ashkenazim. The teacher commits Post Hoc Ergo Propter Hoc, maintaining that because accurate modern machzorim such as Artscroll say that we do 100, therefore that is the way it is, and the earlier machzorim that had other sets were misprints or mistaken.
Just because it's so now, doesn't make it true for the past, though. I went through a number of sources to find out just what was the "old minhag ashkenaz", the "original" custom, and well, there isn't just one, there are quite a lot. However, Artscroll is correct in that 100 has become nearly universally accepted today.
Going back into the past, the Tosafot (12th-century French) bring 40, 60 and 100 as reasonable options and reasons for both. All agree that we do 30 to start out with, since that's the Talmudic minimum (R' Abahu, in Rosh Hashanah 34a). Opinions differ as to which are blown during the repetition of the mussaf amidah, and what is done at the end of services. 40 is brought as the common custom in Franco-Germany (where the Tosafists lived), but they would prefer 60, and they cite the Aruch (earlier Ashkenazic work) that one should blow 100 to fit a Midrash about the 100 sobs that Sisra's mother cried over his death. Rabbenu Tam brings a further variant of 42.
So what are all these variants?
Knock 30 off the top - all agree we do 30 after Torah reading.
After each section of the Musaf: M(alchuyot, Z(ichronot, S(hofarot:
and the blows T(ekiah), S(hevarim), and (te)R(uah), which are grouped as TSRT, TST, or TRT.
10: M-TSRT, Z-TST, S-TRT
12: M-TSRT, Z-TSRT, S-TSRT
30: M-TSRT TST TRT, Z-TSRT TST TRT, S-TSRT TST TRT
And then at the end, either 30, 40, or 10 are blown to make up larger numbers.
So who historically did the various customs?
Tosafot (Rosh Hashanah 33b) list all of the combinations of blasts during the Amidah, so they justify 40, 42, or 60.
RAbN Yarchi (R' Abraham of Lunel, later 12th C.) brings a variety of these customs in his Sefer haManhig (laws of shofar-blowing 20).
One should do the 30 option, but the Sages worried about troubling the congregation, so some do 10. In Sefarad (Christian northern Spain?) and Provence they do [three times] TSRT for Malchuyot, TST for Zichronot, and TRT for Shofarot, making 30. In some parts of France they do TSRT [TST,TRT?] for all three, like R' Yaakov of C. (Corbeil?), and so it is in Champagne and all of Burgundy, doing 30 among all. I hear that in Bavel they do 100, 30 during the silent amidah, 30 during the repetition, and 10 more at the end, to fit the midrash about Sisra's mother. (paraphrased, from Heidenheim machzor note).
So the Western custom was 60, in one variant or another. What about more recent days?
The Shulchan Aruch, recording mostly Sephardic custom in his day, advises 61: 30 at the start, then M-3xTSRT, Z-3xTST, S-3xTRT, or 12, 9 and 9, with the Sephardic Teruah Gedolah at the end.
Our prime witness for Eastern Europe in the 15th century is the Rema, who says that the common custom was 40: (30; 4;3;3) as above. Some would add another 30 at the end, but this was not necessary.
The Vilna Gaon, in the 18th century, seeing value to 60, held that one should blow an extra 20 at the end, bringing the total to 60. So for him, in Lithuania, they were still mostly following the Rema's 40 custom.
In the early 19th century, R' Wolf Heidenheim in Germany produced a set of very accurate machzorim, with a good commentary, on both textual and hermeneutic issues. He produced versions for both Germany (Western Europe) and Poland (Eastern Europe). His machzorim record 42 as the Eastern custom, and 40 as the Western custom, which is still what is printed in current Roedelheim German-custom machzorim today.
The Breuers kehillah in Washington Heights still blows 40 *see below. They then add 30 at the end for a total of 70, and another 30 at mincha for people who missed the morning service. However, another German congregation of my acquaintance does 100, adding 60 at the end to make up the total.
By the end of the 19th century, most poskim were pushing for 100 to become universal. Both the Mishnah Brurah and the Aruch Hashulchan argued for 100, following the Shelah, who was influenced by Kabbalah, which in turn was influenced by the customs of Sephardim. So today, the current Sephardic custom, also used by R' Yosef Dov Soloveitchik, is 30; 10,10,10 in the silent amidah, 10,10,10 in the repeition, and 10 more at the end, making 100. Sephardim add a 101st Teruah Gedolah at the end.
So when Artscroll reports that this is "almost universal", it is correct. However, one is not justified in concluding from that statement that 100 was always the normal custom. The normal customs seem to have been 40, 42 and 60, until 100 years ago.
And if your eyes aren't spinning at the end of all that, you'll have a better understanding of where our shofar blowing came from, and how much you have to make up if you miss part.
1) I am reliably informed that Breuers blows 100, and has at least since the 1980s. 10 during the Amidah, 30 during Full Kaddish, and 30 after Anim Zmirot
2) R' Arie Folger, Chief Rabbi of the Israelitische Gemeinde Basel, tells me that they blow 70.
3) ADDeRabbi: noted & fixed.