Meaning of phrase 手に実際穿った

Question

I'm struggling to understand 手に実際穿った part in the following passage. What meaning does it have?

拡大鏡｛かくだいきょう｝で見て初めて見えてくる文字。うっすらと浮かび上がり、所々｛ところどころ｝かすれて読めない。その文字の形状｛けいじょう｝からして手に実際穿った{じっさいほじった}ような感じである。文字は極めて｛きわめて｝小さい。俺は掠れて｛かすれて｝解読不可能な部分を頭の中で想像補完{そうぞうほかん}し、ひとつの文章を完成させた。

I tried to make a fast translation of the the sentences with the part I cannot grasp, except the part itself.

Letters first became visible when I looked through magnifying glass. Becoming faintly visible, they are scratched here and there which makes them impossible to read in such places. Judging by letters shape it makes the feeling as if 手に実際穿った.

Context: The speaker receives a strange letter, with empty contents. When he tried to look for the fingerprints he seen the print of the whole hand on a letter paper. Now he tried to look through magnifying glass.

Update:

I think now, after remembering all of the context, I more or less understood it. So to the speaker those small letters felt like the writer of the letter drilled them in his hand and then made the hand print on a paper.

Answer 1

Judging from the context you provided, I think it's read as 穿【うが】った, and means "actually carved/engraved on the hand". 穿つ means "to drill", but in this context I feel it's better to translate it as "to carve/engrave" (using something like a chisel/knife, or some similar magical device).

The speaker thought those letters were actually carved/engraved on someone's hand (hmm... like this), and then, stamped on the paper. (i.e., they were not drawn separately on the paper using a pen/brush)

Answer 2

[Edit: this answer was based on the original version of the question which had furigana for the うがつ, rather than ほじる, form of 穿った, so is now obsolete]

I'm reading it as:

".. it felt like the letters were literally drilling into my hands."

That is, 穿つ can mean to pierce/drill/bore. So 手に穿つ is "drill into my hands". Then we can add an adverbial 実際に or just 実際 to make it "literally/really drill into my hands".

The lack of an 'adverbial に' and the adverb being so far "inwards" towards the verb can make it a little harder to parse.